CAB
A cellulosic ester with better moisture resistance, weatherability, and dimensional stability than CA, achieved by adding butyrate groups; chosen for outdoor and optical applications requiring toughness and clarity.
Reference datasheet — CAB is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
CAB grades and fills
CAB is supplied in 3 conditions, soft to hard.
Compare all 3 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
High-plasticizer (soft, high-flow) grade | Pick when maximum toughness, soft touch and easy flow matter more than stiffness or heat resistance (tool handles, dip coatings, flexible tubing). | 18 | 21 | 85 | 63 Shore D |
Low-plasticizer (rigid, high-heat) grade | Choose for maximum stiffness, hardness, dimensional stability and heat-deflection temperature; accepts lower impact strength. | 42 | 44 | 40 | 81 Shore D |
Unplasticized coating/ink resin flake | Solvent-soluble CAB flake used as a flow/levelling, redispersion and hardness additive in automotive coatings, wood lacquers and inks. | 50 | 55 | 12 | 85 Shore D |
Supply forms, finishes and certifications
Ways CAB is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
EXT | Extrusion grade | Supply form |
FDA | Food-contact / medical-compatible grade | Certification |
OPT | Optical / clear sheet and eyewear grade | Grade option |
UV | UV-stabilized / weatherable outdoor grade | Grade option |
STDDefault | Standard (medium-plasticizer) injection-molding grade | Standard supply |
What is CAB?
A cellulosic ester with better moisture resistance, weatherability, and dimensional stability than CA, achieved by adding butyrate groups; chosen for outdoor and optical applications requiring toughness and clarity. CAB has a density of 1.19 g/cm³ (0.043 lb/in³), heavier than 53% of polymer grades. Its glass-transition temperature is 115°C (239 °F). CAB has a yield strength of 28 MPa (4.06 ksi) and a tensile strength of 32 MPa (4.64 ksi) — weaker than 71% of polymer grades. Elongation at break is 60% and the elastic modulus is 1.4 GPa (0.203 Msi).
What is CAB used for?
- tool handles
- steering wheels
- pen barrels
- outdoor signage
- lighting fixtures
- automotive trim
Advantages
- Polishes to a fine finish — 85/100, better than 92% of polymer grades
- Good UV / weathering resistance — 70/100, better than 83% of polymer grades
- Easy to machine — 75/100, better than 78% of polymer grades
- Forms and bends easily — 80/100, better than 75% of polymer grades
Limitations
- Needs corrosion protection — 50/100, worse than 97% of polymer grades
- Absorbs moisture — dry before molding — 1.3%, worse than 88% of polymer grades
- Limited service temperature — 70°C (158 °F), worse than 77% of polymer grades
CAB properties
Typical room-temperature values; bars are the position among polymer grades.
Physical6
CAB has a density of 1.19 g/cm³ (0.043 lb/in³), heavier than 53% of polymer grades. Its glass-transition temperature is 115°C (239 °F).
Mechanical16
CAB has a yield strength of 28 MPa (4.06 ksi) and a tensile strength of 32 MPa (4.64 ksi) — weaker than 71% of polymer grades. Elongation at break is 60% and the elastic modulus is 1.4 GPa (0.203 Msi).
Thermal11
CAB is rated for continuous service to 70°C (158 °F). It conducts heat at 0.2 W/m·K (0.116 BTU/hr·ft·°F), worse than 56% of polymer grades. Thermal expansion is 130 µm/m·K (72.2 µin/in·°F).
Electrical7
CAB is an electrical insulator with a dielectric strength of 16 kV/mm (406.4 V/mil) and a resistivity of 1×10¹² Ω·m.
Chemical & Environmental3
Corrosion resistance is fair (50/100), worse than 97% of polymer grades. UV resistance is very good.
Sustainability4
Producing a kilogram of CAB takes about 105 MJ of energy and emits 4.5 kg of CO₂ — more than 54% of polymer grades. Typical recycled content is 0%.
Manufacturability8
CAB's machinability is very good (75/100, better than 78% of polymer grades); weldability good (60/100); formability very good (80/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the polymer family
Yield strength against density for every polymer grade FabDigit runs. CAB is highlighted; hover a dot for its name, or open the interactive family chart.
Working with CAB
Is CAB easy to machine?
Machines and turns cleanly with sharp positive-rake tools and generous chip clearance; use air or light coolant to avoid heat softening and plasticizer bloom.
Can CAB be welded?
Joins readily by solvent cementing (acetone/MEK blends) or hot-plate/ultrasonic welding; hot-gas welding is possible but degrades easily above ~230 °C.
Can CAB be formed, bent or molded?
Dry 2–3 h at 70–80 °C before molding; melt 175–230 °C, mold 40–80 °C, low back pressure — sheet thermoforms and cold-bends very easily.
CAB chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| butyryl contentwt % of ester substitution; higher butyryl = softer, more solvent-tolerant | 17 – 55 | 37 |
| acetyl contentwt % of ester substitution | 2 – 30 | 13 |
| hydroxyl contentresidual free OH, controls polarity/crosslinkability | 0.8 – 5 | 1.5 |
| plasticizer (e.g. adipate/phthalate/citr0 % in coating flake; 15–25 % in soft molding compounds | 0 – 25 | 12 |
| stabilizers / UV absorber / colorant | 0 – 3 | 1 |
| cellulose backbone (anhydroglucose unitswood pulp / cotton linter derived | balance |
What surface finishes work on CAB?
Buffs to a deep high gloss (classic eyewear finish), takes solvent-based lacquers, printing inks and vacuum metallizing well; avoid aggressive ketone cleaners.
Equivalent designations
Standards and trade names that resolve to CAB in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Similar grades
- D707
How much does CAB cost?
CAB is a premium-cost polymer ($$$), cheaper than about 51% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
CAB — frequently asked
What is CAB used for?
CAB is typically used for tool handles, steering wheels, pen barrels, outdoor signage, lighting fixtures and automotive trim. In short: most weatherable cellulosic; 60 % elongation, tough; best cellulosic for outdoors.
What is the yield strength of CAB?
CAB has a typical yield strength of 28 MPa (4.06 ksi) and a tensile strength of 32 MPa (4.64 ksi) — weaker than 71% of polymer grades. Strength varies by condition: see the 3 listed tempers.
Is CAB easy to machine?
Yes — machinability is rated very good (75/100, better than 78% of polymer grades). Machines and turns cleanly with sharp positive-rake tools and generous chip clearance; use air or light coolant to avoid heat softening and plasticizer bloom.
Can CAB be welded?
Yes — weldability is rated good (60/100). Joins readily by solvent cementing (acetone/MEK blends) or hot-plate/ultrasonic welding; hot-gas welding is possible but degrades easily above ~230 °C.
What surface finishes work on CAB?
Buffs to a deep high gloss (classic eyewear finish), takes solvent-based lacquers, printing inks and vacuum metallizing well; avoid aggressive ketone cleaners.
Can CAB be formed, bent or molded?
Dry 2–3 h at 70–80 °C before molding; melt 175–230 °C, mold 40–80 °C, low back pressure — sheet thermoforms and cold-bends very easily.
What is the maximum service temperature of CAB?
CAB is rated for continuous use to about 70°C (158 °F), and briefly to 95°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does CAB cost?
CAB is a premium-cost polymer ($$$), cheaper than about 51% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM D707 — Standard Specification for Cellulose Acetate Butyrate Molding and Extrusion Compounds — ASTM International (2020)
- ASTM D817 — Test Methods for Cellulose Acetate Propionate and Cellulose Acetate Butyrate — ASTM International (2020)
- Tenite Butyrate cellulosic plastics — property and processing data — Eastman Chemical (2022)
- CAB (cellulose acetate butyrate) coating resins technical data — Eastman Chemical (2021)
- Engineered Materials Handbook Vol. 2: Engineering Plastics — ASM International (1988)
- CAMPUS / Prospector cellulose ester datasets — CWFG / UL Solutions (2024)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.