spore: profile
id: pbt-gf30
spore_version: 0.2
family: polyesters
name: Polybutylene terephthalate, 30% glass fibre reinforced (PBT-GF30)
abbreviation: PBT-GF30
role: Glass-fibre-filled polyester for stiff, dimensionally stable moulded and machined parts
category: composites
type: glass-fiber-reinforced
summary: Polybutylene terephthalate reinforced with 30% glass fibre (PBT-GF30) is a stiff, dimensionally stable polyester for moulded electrical and precision parts. Ensinger's TECADUR PBT GF30 natural prints a tensile modulus of 3400 MPa, and Akro's PRECITE P3 GF 30 natural (6850) prints 10000 MPa, so the two datasheets disagree for the same nominal filler content. Melting temperatures are printed as 224 °C (Ensinger), 225 °C (Akro) and 220 to 230 °C (tbgroup safety information).
best_for: 'Stiff, dimensionally stable moulded and machined parts for electrical and precision uses that stay dry: Akro prints a flexural modulus of 10500 MPa and a heat deflection temperature of 205 °C at 1.8 MPa'
weakest_at: 'Heat and water: Borges et al. 2021 measured 44 MPa tensile strength at 130 °C on specimens dry as supplied, and an equilibrium water uptake of 0.56 % at 130 °C'
identity:
  formula: (C12H12O4)n repeat unit for the polybutylene terephthalate matrix, filled with 30% glass fibre by weight
  cas: 24968-12-5
  source: wikipedia-pbt
  where: Chemical description (repeat unit C12H12O4 and CAS number for PBT); 30% glass fibre from the Ensinger product description. The CAS number is for PBT and no CAS number is printed for the filled grade.
  designations:
    - system: Trade name
      code: TECADUR PBT GF30 natural
      source: ensinger-pbt-gf30
      where: Grade name heading
    - system: Trade name
      code: TECADUR PBT GF30
      source: ensinger-pbt-gf30
      where: Trade name line
    - system: Trade name
      code: PRECITE® P3 GF 30 natural
      source: akro-precite-p3-gf30
      where: Product name heading
    - system: Trade name
      code: PBT GF30
      source: akro-precite-p3-gf30
      where: Designations line
tags:
  environments: []
  stresses:
    - moisture
    - heat
  applications:
    - electronics-and-chips
    - structures
properties:
  - benchmark: elastic_modulus
    label: Modulus of elasticity, tensile test (Ensinger)
    value: 3400
    unit: MPa
    scope: material
    conditions:
      grade: TECADUR PBT GF30 natural
      test_speed: 1 mm/min
      standard: DIN EN ISO 527-2
    method: Typical value printed on the manufacturer product page
    status: ground
    source: ensinger-pbt-gf30
    where: Property table, Modulus of elasticity (tensile test) row
  - benchmark: yield_strength
    label: Tensile strength at yield (Ensinger)
    value: 46
    unit: MPa
    scope: material
    conditions:
      grade: TECADUR PBT GF30 natural
      test_speed: 50 mm/min
      standard: DIN EN ISO 527-2
    method: Typical value printed on the manufacturer product page
    status: ground
    source: ensinger-pbt-gf30
    where: Property table, Tensile strength at yield row
  - benchmark: elongation
    label: Elongation at yield (Ensinger)
    value: 5
    unit: '%'
    scope: material
    conditions:
      grade: TECADUR PBT GF30 natural
      test_speed: 50 mm/min
      standard: DIN EN ISO 527-2
      point: at yield
    method: Typical value printed on the manufacturer product page
    status: ground
    source: ensinger-pbt-gf30
    where: Property table, Elongation at yield (tensile test) row
  - benchmark: elongation
    label: Elongation at break (Ensinger)
    value: 6
    unit: '%'
    scope: material
    conditions:
      grade: TECADUR PBT GF30 natural
      test_speed: 50 mm/min
      standard: DIN EN ISO 527-2
      point: at break
    method: Typical value printed on the manufacturer product page
    status: ground
    source: ensinger-pbt-gf30
    where: Property table, Elongation at break (tensile test) row
  - benchmark: flexural_strength
    label: Flexural strength (Ensinger)
    value: 78
    unit: MPa
    scope: material
    conditions:
      grade: TECADUR PBT GF30 natural
      test_speed: 2 mm/min
      load: 10 N
      standard: DIN EN ISO 178
    method: Typical value printed on the manufacturer product page
    status: ground
    source: ensinger-pbt-gf30
    where: Property table, Flexural strength row
  - benchmark: flexural_modulus
    label: Modulus of elasticity, flexural test (Ensinger)
    value: 3400
    unit: MPa
    scope: material
    conditions:
      grade: TECADUR PBT GF30 natural
      test_speed: 2 mm/min
      load: 10 N
      standard: DIN EN ISO 178
    method: Typical value printed on the manufacturer product page
    status: ground
    source: ensinger-pbt-gf30
    where: Property table, Modulus of elasticity (flexural test) row
  - benchmark: compression_modulus
    label: Compression modulus (Ensinger)
    value: 2800
    unit: MPa
    scope: material
    conditions:
      grade: TECADUR PBT GF30 natural
      test_speed: 5 mm/min
      load: 10 N
      standard: EN ISO 604
    method: Typical value printed on the manufacturer product page
    status: ground
    source: ensinger-pbt-gf30
    where: Property table, Compression modulus row
  - benchmark: charpy_impact_strength
    label: Charpy impact strength (Ensinger)
    value: 37
    unit: kJ/m2
    scope: material
    conditions:
      grade: TECADUR PBT GF30 natural
      standard: DIN EN ISO 179-1eU
      notch: unnotched (eU)
      note_printed: max. 7,5J
    method: Typical value printed on the manufacturer product page
    status: ground
    source: ensinger-pbt-gf30
    where: Property table, Impact strength (Charpy) row
  - benchmark: melting_point
    label: Melting temperature (Ensinger)
    value: 224
    unit: C
    scope: material
    conditions:
      grade: TECADUR PBT GF30 natural
      standard: DIN EN ISO 11357
      unit_as_printed: C
    method: Typical value printed on the manufacturer product page
    status: ground
    source: ensinger-pbt-gf30
    where: Property table, Melting temperature row
  - benchmark: thermal_conductivity
    label: Thermal conductivity (Ensinger)
    value: 0.33
    unit: W/(k*m)
    scope: material
    conditions:
      grade: TECADUR PBT GF30 natural
      unit_as_printed: W/(k*m)
    method: Typical value printed on the manufacturer product page; the page cites ISO 22007-4:2008 as the method
    status: ground
    source: ensinger-pbt-gf30
    where: Property table, Thermal conductivity row
  - benchmark: specific_heat
    label: Specific heat (Ensinger)
    value: 1.2
    unit: J/(g*K)
    scope: material
    conditions:
      grade: TECADUR PBT GF30 natural
      unit_as_printed: J/(g*K)
    method: Typical value printed on the manufacturer product page; the page cites ISO 22007-4:2008 as the method
    status: ground
    source: ensinger-pbt-gf30
    where: Property table, Specific heat row
  - benchmark: max_service_temp
    label: Service temperature, short term (Ensinger)
    value: 200
    unit: °C
    scope: material
    conditions:
      grade: TECADUR PBT GF30 natural
      duration: short term
    method: Typical value printed on the manufacturer product page; the page gives no test standard
    status: ground
    source: ensinger-pbt-gf30
    where: Property table, Service temperature row (short term)
  - benchmark: max_service_temp
    label: Service temperature, long term (Ensinger)
    value: 110
    unit: °C
    scope: material
    conditions:
      grade: TECADUR PBT GF30 natural
      duration: long term
    method: Typical value printed on the manufacturer product page; the page gives no test standard
    status: ground
    source: ensinger-pbt-gf30
    where: Property table, Service temperature row (long term)
  - benchmark: density
    label: Density (Ensinger)
    value: 1.46
    unit: g/cm3
    scope: material
    conditions:
      grade: TECADUR PBT GF30 natural
      temperature: not printed
    method: Value printed in the Facts section of the manufacturer product page; no test standard printed
    status: ground
    source: ensinger-pbt-gf30
    where: Facts section, Density
  - benchmark: moisture_absorption
    label: Water absorption after 24 h (Ensinger)
    value: 0.02
    unit: '%'
    scope: material
    conditions:
      grade: TECADUR PBT GF30 natural
      time: 24 h
      temperature: 23 °C
    method: Typical value printed on the manufacturer product page; standard DIN EN ISO 62 printed
    status: ground
    source: ensinger-pbt-gf30
    where: Property table, Water absorption row (24h)
  - benchmark: moisture_absorption
    label: Water absorption after 96 h (Ensinger)
    value: 0.04
    unit: '%'
    scope: material
    conditions:
      grade: TECADUR PBT GF30 natural
      time: 96 h
      temperature: 23 °C
    method: Typical value printed on the manufacturer product page; standard DIN EN ISO 62 printed
    status: ground
    source: ensinger-pbt-gf30
    where: Property table, Water absorption row (96h)
  - benchmark: elastic_modulus
    label: Tensile modulus (Akro)
    value: 10000
    unit: MPa
    scope: material
    conditions:
      grade: PRECITE P3 GF 30 natural (6850)
      test_speed: 1 mm/min
      condition_printed: d.a.m.
      standard: ISO 527-2
    method: Typical value printed on the manufacturer product page
    status: ground
    source: akro-precite-p3-gf30
    where: Property table, Tensile modulus row
  - benchmark: ultimate_tensile_strength
    label: Tensile stress at break (Akro)
    value: 145
    unit: MPa
    scope: material
    conditions:
      grade: PRECITE P3 GF 30 natural (6850)
      test_speed: 5 mm/min
      condition_printed: d.a.m.
      standard: ISO 527-2
    method: Typical value printed on the manufacturer product page
    status: ground
    source: akro-precite-p3-gf30
    where: Property table, Tensile stress at break row
  - benchmark: elongation
    label: Tensile strain at break (Akro)
    value: 3
    unit: '%'
    scope: material
    conditions:
      grade: PRECITE P3 GF 30 natural (6850)
      test_speed: 5 mm/min
      condition_printed: d.a.m.
      standard: ISO 527-2
      point: at break
    method: Typical value printed on the manufacturer product page
    status: ground
    source: akro-precite-p3-gf30
    where: Property table, Tensile strain at break row
  - benchmark: flexural_modulus
    label: Flexural modulus (Akro)
    value: 10500
    unit: MPa
    scope: material
    conditions:
      grade: PRECITE P3 GF 30 natural (6850)
      test_speed: 2 mm/min
      condition_printed: d.a.m.
      standard: ISO 178
    method: Typical value printed on the manufacturer product page
    status: ground
    source: akro-precite-p3-gf30
    where: Property table, Flexural modulus row
  - benchmark: flexural_strength
    label: Flexural strength (Akro)
    value: 230
    unit: MPa
    scope: material
    conditions:
      grade: PRECITE P3 GF 30 natural (6850)
      test_speed: 2 mm/min
      condition_printed: d.a.m.
      standard: ISO 178
    method: Typical value printed on the manufacturer product page
    status: ground
    source: akro-precite-p3-gf30
    where: Property table, Flexural strength row
  - benchmark: charpy_impact_strength
    label: Charpy impact strength (Akro)
    value: 65
    unit: kJ/m2
    scope: material
    conditions:
      grade: PRECITE P3 GF 30 natural (6850)
      standard: ISO 179-1/1eU
      temperature: 23 °C
      condition_printed: d.a.m.
    method: Typical value printed on the manufacturer product page
    status: ground
    source: akro-precite-p3-gf30
    where: Property table, Charpy impact strength row
  - benchmark: charpy_notched_impact_strength
    label: Charpy notched impact strength (Akro)
    value: 11
    unit: kJ/m2
    scope: material
    conditions:
      grade: PRECITE P3 GF 30 natural (6850)
      standard: ISO 179-1/1eA
      temperature: 23 °C
      condition_printed: d.a.m.
    method: Typical value printed on the manufacturer product page
    status: ground
    source: akro-precite-p3-gf30
    where: Property table, Charpy notched impact strength row
  - benchmark: heat_deflection_temperature
    label: Heat deflection temperature, HDT/A (Akro)
    value: 205
    unit: °C
    scope: material
    conditions:
      grade: PRECITE P3 GF 30 natural (6850)
      load: 1.8 MPa
      standard: ISO 75 (HDT/A)
    method: Typical value printed on the manufacturer product page
    status: ground
    source: akro-precite-p3-gf30
    where: Property table, Temperature of deflection under load HDT/A row
  - benchmark: melting_point
    label: Melting temperature (Akro)
    value: 225
    unit: °C
    scope: material
    conditions:
      grade: PRECITE P3 GF 30 natural (6850)
      standard: ISO 11357-3
      method_printed: DSC, 10 K/min
    method: Typical value printed on the manufacturer product page
    status: ground
    source: akro-precite-p3-gf30
    where: Property table, Melting temperature row
  - benchmark: density
    label: Density (Akro)
    value: 1.53
    unit: g/cm³
    scope: material
    conditions:
      grade: PRECITE P3 GF 30 natural (6850)
      standard: ISO 1183
      temperature: 23 °C
      printed_form: 1,53 g/cm³
    method: Typical value printed on the manufacturer product page, with the ISO 1183 standard printed
    status: ground
    source: akro-precite-p3-gf30
    where: Property table, Density row
  - benchmark: moisture_absorption
    label: Humidity absorption (Akro)
    value: 0.2
    unit: '%'
    scope: material
    conditions:
      grade: PRECITE P3 GF 30 natural (6850)
      standard: ISO 1110
      temperature: 70 °C
      relative_humidity: 62 %
    method: Typical value printed on the manufacturer product page
    status: ground
    source: akro-precite-p3-gf30
    where: Property table, Humidity absorption row
  - benchmark: mould_shrinkage_flow
    label: Moulding shrinkage, flow direction (Akro)
    value: 0.3
    unit: '%'
    scope: material
    conditions:
      grade: PRECITE P3 GF 30 natural (6850)
      standard: ISO 294-4
      direction: flow
    method: Typical value printed on the manufacturer product page
    status: ground
    source: akro-precite-p3-gf30
    where: Property table, Molding shrinkage (flow) row
  - benchmark: mould_shrinkage_transverse
    label: Moulding shrinkage, transverse direction (Akro)
    value: 0.9
    unit: '%'
    scope: material
    conditions:
      grade: PRECITE P3 GF 30 natural (6850)
      standard: ISO 294-4
      direction: transverse
    method: Typical value printed on the manufacturer product page
    status: ground
    source: akro-precite-p3-gf30
    where: Property table, Molding shrinkage (transverse) row
  - benchmark: comparative_tracking_index
    label: Comparative tracking index (Akro)
    value: 350
    unit: V
    scope: material
    conditions:
      grade: PRECITE P3 GF 30 natural (6850)
      standard: IEC 60112
      test_liquid: A
    method: Typical value printed on the manufacturer product page
    status: ground
    source: akro-precite-p3-gf30
    where: Property table, Comparative tracking index row
  - benchmark: melt_volume_rate
    label: Melt volume rate (Akro)
    value: 9
    unit: cm3/10 min
    scope: material
    conditions:
      grade: PRECITE P3 GF 30 natural (6850)
      standard: ISO 1133
      temperature: 250 °C
      load: 2.16 kg
    method: Typical value printed on the manufacturer product page
    status: ground
    source: akro-precite-p3-gf30
    where: Property table, MVR row
  - benchmark: moisture_absorption
    label: Equilibrium water uptake at 35 °C (Borges et al.)
    value: 0.47
    unit: '%'
    scope: material
    conditions:
      material: PBT-GF30 as tested in Borges et al. (grade not named)
      test: water immersion, equilibrium M-infinity
      temperature: 35 °C
    method: Measured in water immersion and printed in Table 2 of the paper
    status: ground
    source: borges-2021
    where: Table 2, row T 35 °C, M∞ (%)
  - benchmark: moisture_absorption
    label: Equilibrium water uptake at 70 °C (Borges et al.)
    value: 0.5
    unit: '%'
    scope: material
    conditions:
      material: PBT-GF30 as tested in Borges et al. (grade not named)
      test: water immersion, equilibrium M-infinity
      temperature: 70 °C
    method: Measured in water immersion and printed in Table 2 of the paper
    status: ground
    source: borges-2021
    where: Table 2, row T 70 °C, M∞ (%)
  - benchmark: moisture_absorption
    label: Equilibrium water uptake at 130 °C (Borges et al.)
    value: 0.56
    unit: '%'
    scope: material
    conditions:
      material: PBT-GF30 as tested in Borges et al. (grade not named)
      test: water immersion, equilibrium M-infinity
      temperature: 130 °C
    method: Measured in water immersion and printed in Table 2 of the paper
    status: ground
    source: borges-2021
    where: Table 2, row T 130 °C, M∞ (%)
  - benchmark: elastic_modulus
    label: Young's modulus, room temperature, standard specimens (Borges et al.)
    value: 8.6
    unit: GPa
    scope: material
    conditions:
      material: PBT-GF30 as tested in Borges et al. (grade not named)
      condition: dry as supplied
      temperature: room temperature
      specimen: standard
    method: Bulk tensile test printed in the mechanical properties text, tensile rate 1 mm/min
    status: ground
    uncertainty: ± 0.1 GPa (printed)
    source: borges-2021
    where: Mechanical properties, room temperature standard specimens
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, room temperature, standard specimens (Borges et al.)
    value: 112
    unit: MPa
    scope: material
    conditions:
      material: PBT-GF30 as tested in Borges et al. (grade not named)
      condition: dry as supplied
      temperature: room temperature
      specimen: standard
    method: Bulk tensile test printed in the mechanical properties text, tensile rate 1 mm/min
    status: ground
    uncertainty: ± 1 MPa (printed)
    source: borges-2021
    where: Mechanical properties, room temperature standard specimens
  - benchmark: elastic_modulus
    label: Young's modulus at 70 °C (Borges et al.)
    value: 4.6
    unit: GPa
    scope: material
    conditions:
      material: PBT-GF30 as tested in Borges et al. (grade not named)
      condition: dry as supplied, tested at temperature
      temperature: 70 °C
    method: Bulk tensile test printed in the mechanical properties table
    status: ground
    uncertainty: ± 0.1 GPa (printed)
    source: borges-2021
    where: Mechanical properties table, row 70 °C
  - benchmark: ultimate_tensile_strength
    label: Tensile strength at 70 °C (Borges et al.)
    value: 66
    unit: MPa
    scope: material
    conditions:
      material: PBT-GF30 as tested in Borges et al. (grade not named)
      condition: dry as supplied, tested at temperature
      temperature: 70 °C
    method: Bulk tensile test printed in the mechanical properties table
    status: ground
    uncertainty: ± 1 MPa (printed)
    source: borges-2021
    where: Mechanical properties table, row 70 °C
  - benchmark: elastic_modulus
    label: Young's modulus at 130 °C (Borges et al.)
    value: 2.3
    unit: GPa
    scope: material
    conditions:
      material: PBT-GF30 as tested in Borges et al. (grade not named)
      condition: dry as supplied, tested at temperature
      temperature: 130 °C
    method: Bulk tensile test printed in the mechanical properties table
    status: ground
    uncertainty: ± 0.1 GPa (printed)
    source: borges-2021
    where: Mechanical properties table, row 130 °C
  - benchmark: ultimate_tensile_strength
    label: Tensile strength at 130 °C (Borges et al.)
    value: 44
    unit: MPa
    scope: material
    conditions:
      material: PBT-GF30 as tested in Borges et al. (grade not named)
      condition: dry as supplied, tested at temperature
      temperature: 130 °C
    method: Bulk tensile test printed in the mechanical properties table
    status: ground
    uncertainty: ± 1 MPa (printed)
    source: borges-2021
    where: Mechanical properties table, row 130 °C
  - benchmark: glass_transition_temperature
    label: Glass transition temperature (Borges et al.)
    value: 49
    unit: °C
    scope: material
    conditions:
      material: PBT-GF30 as tested in Borges et al. (grade not named)
    method: Value printed in the Borges et al. 2021 test conditions section
    status: ground
    uncertainty: ± 4 °C (printed)
    source: borges-2021
    where: Test conditions, glass transition temperature Tg
  - benchmark: density
    label: Density, safety information range (tbgroup)
    value: 1.3
    value_high: 1.8
    bound: range
    unit: g/ccm
    scope: material
    conditions:
      grade: PBT GF30, supplier safety information
      unit_as_printed: g/ccm
    method: Range printed in the supplier safety information (not a datasheet value)
    status: ground
    source: tbgroup-pbt-sds
    where: Section 9.2, Density PBT GF30
  - benchmark: melting_point
    label: Melting point, safety information range (tbgroup)
    value: 220
    value_high: 230
    bound: range
    unit: °C
    scope: material
    conditions:
      grade: PBT GF30, supplier safety information
    method: Range printed in the supplier safety information (not a datasheet value)
    status: ground
    source: tbgroup-pbt-sds
    where: Section 9.2, Melting point
  - benchmark: flash_point
    label: Flash point (tbgroup)
    value: 400
    bound: lower
    unit: °C
    scope: material
    conditions:
      grade: PBT GF30, supplier safety information
      printed_as: '> 400 °C'
    method: Value printed in the supplier safety information as a lower bound
    status: ground
    source: tbgroup-pbt-sds
    where: Section 9.2, Flash point
  - benchmark: ignition_point
    label: Ignition point (tbgroup)
    value: 350
    bound: lower
    unit: °C
    scope: material
    conditions:
      grade: PBT GF30, supplier safety information
      printed_as: '> 350 °C'
    method: Value printed in the supplier safety information as a lower bound
    status: ground
    source: tbgroup-pbt-sds
    where: Section 9.2, Ignition point
  - benchmark: thermal_decomposition_onset
    label: Thermal decomposition onset (tbgroup)
    value: 290
    bound: lower
    unit: °C
    scope: material
    conditions:
      grade: PBT GF30, supplier safety information
      printed_as: '> 290 °C'
    method: Value printed in the supplier safety information as a lower bound
    status: ground
    source: tbgroup-pbt-sds
    where: Section 10, Stability and reactivity, thermal decomposition
corrosion:
  - environment: Hot water above 60 °C
    headline: PBT is sensitive to hot water above 60 °C, according to Wikipedia.
    effect: Wikipedia states that PBT and PET are sensitive to hot water above 60 °C (140 °F). The page does not use the word hydrolysis, and it gives no test condition or glass-fibre content for this statement.
    rating: moderate
    conditions:
      basis: general statement for PBT, not tested on this grade
    source: wikipedia-pbt
    where: Chemical and physical properties, hot water statement
  - environment: Water immersion at 35 °C, 70 °C and 130 °C
    headline: Equilibrium water uptake rises from 0.47 % at 35 °C to 0.56 % at 130 °C in PBT-GF30 tested by Borges et al.
    effect: Borges et al. 2021 state that the water diffusion behaviour is Fickian, and print equilibrium uptake M-infinity values of 0.47 %, 0.50 % and 0.56 % at 35, 70 and 130 °C. The paper says tensile values after water ageing appear only in a figure.
    rating: moderate
    conditions:
      material: PBT-GF30 as tested in Borges et al. (grade not named)
      test: water immersion
    source: borges-2021
    where: Table 2 and Section 3.3 (Fick's law statement)
  - environment: Heat and water together above 80 °C
    headline: Borges et al. report a chemical change in the OH profile between 80 and 85 °C.
    effect: Borges et al. report that the OH⁻ profile change in FTIR occurs between 80 and 85 °C, which the paper treats as the point where the chemical change becomes visible. The paper prints no mass loss figure for this effect.
    rating: moderate
    conditions:
      material: PBT-GF30 as tested in Borges et al. (grade not named)
      test: FTIR after water exposure
    source: borges-2021
    where: Test conditions, chemical change (FTIR)
  - environment: Changing climate with low moisture absorption
    headline: Akro states that the grade has low moisture absorption, giving consistent properties in changing climates.
    effect: Akro states that low moisture absorption gives consistent mechanical and electrical properties under changing climatic conditions. The page gives the 0.2 % and 0.4 % absorption values recorded in the properties table, and no ageing test.
    rating: low
    conditions:
      basis: manufacturer statement with absorption values from the property table
    source: akro-precite-p3-gf30
    where: Product description
risks:
  hazards:
    - text: Not classified under the Dangerous Chemicals Ordinance or relevant EC Guidelines, and the safety information lists no hazardous ingredients.
      ghs: []
      source: tbgroup-pbt-sds
      where: 'Section 2.2 (hazardous ingredients: None), Section 3 (Potential hazards: None), Section 15 (Regulations)'
    - text: Dust from mechanical processing, such as grinding, may form an explosible dust-air mixture if dispersed.
      ghs: []
      source: tbgroup-pbt-sds
      where: Section 7, precautions against fire and explosion
    - text: Molten material can cause burns, and the first-aid section states that burns caused by molten material require medical care.
      ghs: []
      source: tbgroup-pbt-sds
      where: Section 4, First-aid measures
  failure_risks:
    - mode: Thermal decomposition at high temperature
      trigger: Heating above 290 °C during processing or in a fire
      consequence: Toxic gases, including traces of hydrogen cyanide, carbon monoxide, tetrahydrofuran and terephthalic acid, are possibly released above 290 °C (tbgroup safety information).
      severity: high
      source: tbgroup-pbt-sds
      where: Section 5 and Section 10
    - mode: Loss of stiffness and strength at elevated temperature
      trigger: Use above room temperature (Borges et al. tested dry specimens at the test temperature)
      consequence: Young's modulus falls to 4.6 GPa at 70 °C and 2.3 GPa at 130 °C, and tensile strength falls to 66 MPa at 70 °C and 44 MPa at 130 °C, against 8.6 GPa and 112 MPa at room temperature (dry as supplied).
      severity: moderate
      source: borges-2021
      where: Mechanical properties table, rows 70 °C and 130 °C
  side_effects: []
  handling:
    - text: Provide adequate ventilation and local exhaust as needed, and withdraw dust by suction, according to the safety information.
      source: tbgroup-pbt-sds
      where: Section 7, advices on safe handling
    - text: Take precautionary measures against static discharges and keep away from sources of ignition during processing.
      source: tbgroup-pbt-sds
      where: Section 7, precautions against fire and explosion
  mitigations: []
uses:
  - application: electronics-and-chips
    device: Electrical and precision moulded parts
    example: Akro lists PRECITE P3 GF 30 natural (6850) for precision parts in automotive, mechanical engineering, electrical and electronic, and household goods, and cites low moisture absorption for consistent electrical properties.
    source: akro-precite-p3-gf30
    where: Product description
  - application: structures
    device: Dimensionally stable moulded and machined engineering parts
    example: Ensinger describes TECADUR PBT GF30 natural as having very high rigidity, mechanical strength, creep strength and dimensional stability, and notes that it is less suitable for sliding applications.
    source: ensinger-pbt-gf30
    where: Product description
supply:
  - subject: Terephthalic acid (monomer)
    abundance: Wikipedia states that several million tons are produced annually, with no year or tonnage printed.
    producers: []
    critical_lists: []
    substitutes: []
    source: wikipedia-terephthalic-acid
    where: Production section, catalytic oxidation of p-xylene; Several million tons are produced annually
  - subject: 1,4-Butanediol (monomer)
    abundance: Wikipedia states that about one million metric tons per year are produced worldwide, with no year printed for that figure.
    producers: []
    critical_lists: []
    substitutes: []
    source: wikipedia-butanediol
    where: Industrial production and production volume sections
  - subject: Glass fibre (reinforcement)
    abundance: Wikipedia gives no production figure for glass fibre. It describes E-glass as an alumino-borosilicate glass with less than 1% w/w alkali oxides, mainly used for glass-reinforced plastics.
    producers: []
    critical_lists: []
    substitutes: []
    source: wikipedia-glass-fiber
    where: Fibre formation section and Chemistry section
documents:
  - title: TECADUR PBT GF30 natural, Ensinger product page
    type: datasheet
    url: https://www.ensingerplastics.com/en/shapes/tecadur-pbt-gf30-natural
  - title: PRECITE P3 GF 30 natural (6850), Akro product page
    type: datasheet
    url: https://akro-plastic.com/en/product/precite-p3-gf-30-natural-6850-en
  - title: Safety information, Polybutylene Terephthalate (PBT), TBGroup
    type: sds
    url: https://www.technoform.com/sites/default/files/2021-02/tbgroup-do-tb-13_-_safety_information_pbt.pdf
    year: 2021
  - title: Borges et al., Effect of Water Ingress on the Mechanical and Chemical Properties of Polybutylene Terephthalate Reinforced with Glass Fibers, Materials (Basel) 14(5), 1261
    type: paper
    url: https://pmc.ncbi.nlm.nih.gov/articles/PMC7961491
    year: 2021
gaps:
  - 'UNS and EN designations: neither manufacturer page prints a UNS or EN number, and none was found in any source read in this run.'
  - 'PubChem record for polybutylene terephthalate: the PubChem page returned a browser check and could not be read, so no GHS classification from PubChem is recorded.'
  - 'Coefficient of thermal expansion from Ensinger (8 and 10, printed as 10-5*1/K): the printed exponent form is not recorded.'
  - 'Surface resistivity from Ensinger (printed 1014 Ω) and from Akro (printed 1012 Ω): the exponent is lost in the page text, so neither value is recorded.'
  - 'Volume resistivity from Akro, printed as > 1013 Ω x cm: exponent form, not recorded.'
  - 'Diffusion coefficients from Borges et al. Table 2 (printed as 3.15×10−13 m2/s and similar): exponent form, not recorded.'
  - 'The density values disagree: Ensinger prints 1.46 g/cm3 with no test standard, Akro prints 1,53 g/cm³ per ISO 1183, and the tbgroup safety information prints 1.3 to 1.8 g/ccm for PBT GF30. All three are recorded and none is a test value for a common grade.'
  - 'Tensile strength and elongation of the Borges et al. specimens after water ageing: these appear only in Figure 11 with no numbers in the text, so no values are recorded.'
  - Relative humidity for the 130 °C water test is not printed in Borges et al.; the paper states that a water container was kept open in the chamber.
  - Borges et al. do not name the PBT-GF30 grade they tested, so their values are not attributed to TECADUR or PRECITE.
  - UL 94 flammability (Ensinger prints HB) is not numeric and is not recorded as a property.
  - 'Glass fibre oxide composition: the Wikipedia Glass fiber article gives no oxide-by-oxide percentages, so no composition values are recorded.'
  - 'Glass fibre content range in glass-reinforced plastics: the Wikipedia article prints no percentage range.'
  - 'Producer tonnages and country shares for PBT-GF30 or for PBT: not found in any source read. USGS Mineral Commodity Summaries do not cover this polymer.'
  - 'Hydrolysis ageing data for PBT-GF30 with retention figures after humid ageing: the BASF moisture PDF could not be read, and the AGH and Fraunhofer results were only seen in search summaries, so no values from them are recorded.'
  - 'Space behaviour (atomic oxygen, outgassing, UV, radiation) for PBT-GF30: no source for this grade was read in this run.'
  - 'Akro water absorption, saturated (ISO 62, 23 °C), printed as 0,4 % with a decimal comma: the value check cannot match a decimal comma, so the row is not recorded.'
  - 'Non-canonical benchmark names used because no canonical name exists: charpy_impact_strength, charpy_notched_impact_strength, compression_modulus, mould_shrinkage_flow, mould_shrinkage_transverse, comparative_tracking_index, melt_volume_rate, ignition_point, thermal_decomposition_onset.'
sources:
  ensinger-pbt-gf30:
    title: TECADUR PBT GF30 natural, Ensinger product page (typical values)
    id: Product page, property table, Facts section (density)
    url: https://www.ensingerplastics.com/en/shapes/tecadur-pbt-gf30-natural
    kind: datasheet
    license: manufacturer web page, linked not reproduced
  akro-precite-p3-gf30:
    title: PRECITE P3 GF 30 natural (6850), Akro product page (typical values)
    id: Product page, property table and product description
    url: https://akro-plastic.com/en/product/precite-p3-gf-30-natural-6850-en
    kind: datasheet
    license: manufacturer web page, linked not reproduced
  tbgroup-pbt-sds:
    title: Safety information, Polybutylene Terephthalate (PBT), TBGroup, version 2
    id: TBGroup-Do-TB-13 version 2.01.2021, Sections 2, 3, 4, 5, 7, 9.2, 10 and 15
    url: https://www.technoform.com/sites/default/files/2021-02/tbgroup-do-tb-13_-_safety_information_pbt.pdf
    year: 2021
    kind: datasheet
    license: supplier safety information, linked not reproduced
  borges-2021:
    title: Effect of Water Ingress on the Mechanical and Chemical Properties of Polybutylene Terephthalate Reinforced with Glass Fibers
    id: Borges, Akhavan-Safar, Marques, Carbas, Ueffing, Weissgraeber and da Silva, Materials (Basel) 14(5), 1261; doi 10.3390/ma14051261; full text read as Europe PMC XML for PMC7961491 (article page https://pmc.ncbi.nlm.nih.gov/articles/PMC7961491)
    url: https://www.ebi.ac.uk/europepmc/webservices/rest/PMC7961491/fullTextXML
    year: 2021
    kind: paper
    license: open access article, linked not reproduced
  wikipedia-pbt:
    title: Polybutylene terephthalate, Wikipedia
    id: Polybutylene terephthalate article, Chemical description, Glass-fibre and chemical resistance statements, hot water statement
    url: https://en.wikipedia.org/wiki/Polybutylene_terephthalate
    kind: web
    license: CC BY-SA 4.0, linked not reproduced
  wikipedia-glass-fiber:
    title: Glass fiber, Wikipedia
    id: Glass fiber article, fibre formation, chemistry, sizing and GRP sections
    url: https://en.wikipedia.org/wiki/Glass_fiber
    kind: web
    license: CC BY-SA 4.0, linked not reproduced
  wikipedia-terephthalic-acid:
    title: Terephthalic acid, Wikipedia
    id: Terephthalic acid article, Production and Uses sections
    url: https://en.wikipedia.org/wiki/Terephthalic_acid
    kind: web
    license: CC BY-SA 4.0, linked not reproduced
  wikipedia-butanediol:
    title: 1,4-Butanediol, Wikipedia
    id: 1,4-Butanediol article, Industrial production and Uses sections
    url: https://en.wikipedia.org/wiki/1,4-Butanediol
    kind: web
    license: CC BY-SA 4.0, linked not reproduced
  nist-carbon:
    title: NIST Atomic Weights and Isotopic Compositions for All Elements, carbon
    id: Standard atomic weight table, element C, atomic number 6
    url: https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=C&all=all&ascii=html
    kind: database
    license: US government data
  nist-hydrogen:
    title: NIST Atomic Weights and Isotopic Compositions for All Elements, hydrogen
    id: Standard atomic weight table, element H, atomic number 1
    url: https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=H&all=all&ascii=html
    kind: database
    license: US government data
  nist-oxygen:
    title: NIST Atomic Weights and Isotopic Compositions for All Elements, oxygen
    id: Standard atomic weight table, element O, atomic number 8
    url: https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=O&all=all&ascii=html
    kind: database
    license: US government data
license: CC-BY-4.0
updated: '2026-11-01'
review:
  status: draft
  method: assistant
  checked_values: 46
  unreachable: 1
  caveats: 4
  note: Values were read by an AI assistant on 2026-11-01 from the pages named in each entry. The Ensinger and Akro values are typical values printed on manufacturer pages, with no test standard printed for the Ensinger density. Borges et al. did not name the grade they tested. PubChem could not be read. The tbgroup values are supplier safety information, not datasheet values.
story:
  recipe:
    line: Polybutylene terephthalate is made by polymerising 1,4-butanediol with terephthalic acid, and its repeat unit is C12H12O4 (Wikipedia). This grade is a PBT matrix filled with 30% glass fibre by weight (Ensinger). Wikipedia states that a size is applied to glass fibre after drawing in the continuous filament process, to protect the fibre and to give it affinity for a resin.
    parts:
      - name: Polybutylene terephthalate matrix
        role: Semicrystalline polyester matrix, repeat unit C12H12O4
        share_note: balance
        source: wikipedia-pbt
        where: Chemical description
      - name: Glass fibre
        role: Reinforcing filler at 30% by weight in this grade
        share_percent: 30
        source: ensinger-pbt-gf30
        where: Product description
      - name: Carbon
        symbol: C
        role: Carbon atoms in the PBT repeat unit C12H12O4
        source: nist-carbon
        where: Standard atomic weight table
      - name: Hydrogen
        symbol: H
        role: Hydrogen atoms in the PBT repeat unit C12H12O4
        source: nist-hydrogen
        where: Standard atomic weight table
      - name: Oxygen
        symbol: O
        role: Oxygen atoms in the PBT repeat unit C12H12O4
        source: nist-oxygen
        where: Standard atomic weight table
  risk_groups:
    - title: For people
      lead: The one safety information sheet read classifies this grade as not hazardous under the cited EC rules.
      level: 1
      verdict: Not classified in the safety sheet read
      points:
        - label: Classification
          line: 'The tbgroup safety information prints Potential hazards: None and states that the product is not classified by the Dangerous Chemicals Ordinance or EC guidelines.'
        - label: Dust
          line: Dust from grinding may form an explosible dust-air mixture if dispersed, so dust is removed by suction.
    - title: If it fails
      lead: The failure routes in these sources are heat and water, and the heat route releases toxic gases.
      level: 3
      verdict: Heat above 290 °C releases toxic gases
      points:
        - label: Heat
          line: Above 290 °C the product may release toxic gases, including traces of hydrogen cyanide, according to the safety information.
        - label: Water
          line: Borges et al. measured an equilibrium water uptake of 0.56 % at 130 °C, and tensile strength of 44 MPa at 130 °C on dry specimens.
  why: Polybutylene terephthalate with 30% glass fibre (PBT-GF30) is a stiff, dimensionally stable moulded polymer. Ensinger's TECADUR PBT GF30 natural prints a tensile modulus of 3400 MPa and a melting temperature of 224 °C. Akro's PRECITE P3 GF 30 natural (6850) prints a tensile modulus of 10000 MPa, a heat deflection temperature of 205 °C at 1.8 MPa, and a density of 1.53 g/cm³. The two datasheets disagree, so both values are shown.
  can_do:
    - label: Stiff under load
      line: Akro prints a flexural modulus of 10500 MPa and a flexural strength of 230 MPa for PRECITE P3 GF 30 natural (6850), both per ISO 178 at 2 mm/min.
      benchmark: flexural_modulus
    - label: Hold its shape with heat
      line: Akro prints a heat deflection temperature (HDT/A) of 205 °C at 1.8 MPa for the same grade, per ISO 75.
      benchmark: heat_deflection_temperature
    - label: Keep strength when hot and wet
      line: Borges et al. measured 44 MPa tensile strength at 130 °C on specimens dry as supplied, and 0.56 % equilibrium water uptake at 130 °C, for a PBT-GF30 whose grade they do not name.
      benchmark: ultimate_tensile_strength
  compare: Two datasheets for the same 30% glass-fibre PBT disagree. Ensinger prints a tensile modulus of 3400 MPa in a DIN EN ISO 527-2 test and a density of 1.46 g/cm3 with no test standard, while Akro prints 10000 MPa per ISO 527-2 and a density of 1.53 g/cm³ per ISO 1183. Borges et al. report 8.6 GPa at room temperature for a PBT-GF30 whose grade is not named. Read the rows as values for different grades and test methods, not as a ranking.
  compare_rows:
    - scope: material
      label: Density
      benchmark: density
    - scope: material
      label: Tensile modulus
      benchmark: elastic_modulus
    - scope: material
      label: Heat deflection temperature
      benchmark: heat_deflection_temperature
  handling:
    - Specify the grade, since Ensinger and Akro print different tensile moduli for PBT-GF30.
    - Check the current supplier safety information before processing, because the data cited here are supplier information and not a warranty of properties.
    - Keep dust out of the work area, because processing dust may form an explosible dust-air mixture.
  good_for:
    - 'Stiff moulded parts: Akro prints a flexural modulus of 10500 MPa for PRECITE P3 GF 30 natural (6850).'
    - 'Dimensionally stable parts: Akro prints moulding shrinkage of 0.3 % (flow) and 0.9 % (transverse) per ISO 294-4.'
    - 'Electrical parts that stay dry: Akro prints a comparative tracking index of 350 V per IEC 60112 and a low water absorption.'
  watch_out:
    - 'Water: Borges et al. measured 0.47 % equilibrium uptake at 35 °C, rising to 0.56 % at 130 °C, and report that the tensile values after water ageing are only in a figure.'
    - 'Heat: the tensile strength falls to 66 MPa at 70 °C and 44 MPa at 130 °C on dry specimens, against 112 MPa at room temperature.'
    - Thermal decomposition starts above 290 °C and releases toxic gases, including traces of hydrogen cyanide.
    - No outgassing, radiation or atomic oxygen data for this grade was found, so no space behaviour is recorded.
  verdict: 'PBT-GF30 is a stiff moulded polymer with a flexural modulus of 10500 MPa and a heat deflection temperature of 205 °C at 1.8 MPa in the Akro grade read. The Ensinger grade reads 3400 MPa tensile modulus, so the two datasheets differ. Its weak point is hot water: Borges et al. report 0.56 % equilibrium water uptake at 130 °C and 44 MPa tensile strength at 130 °C.'