Chemical Name

Cellulose Diacetate

Produced by partial esterification of natural cellulose

Degree of Substitution (DS)

2.2–2.5

Theoretical maximum DS = 3; diacetate indicates partial substitution of hydroxyl groups by acetyl groups

Acetyl Content

29–34 wt%

Higher DS corresponds to higher acetyl content

Purity / Main Component Content

≥ 99% (dry basis)

Industrial grade typically ≥ 99%

pH (10% ethanol solution)

5.0–7.0

Generally neutral to slightly acidic

Ash Content

≤ 0.05%

Industrial grade commonly ≤ 0.1%

Appearance

Transparent to milky-white flakes

Sheet/flake form, free of visible impurities

Density

1.28–1.30 g/cm³

At room temperature

Glass Transition Temperature (Tg)

≈ 185–200°C

CDA exhibits relatively high rigidity

Melting / Softening Point

~230–260°C (decomposition begins)

No true melting point; decomposes upon heating

Moisture Content

2.0–6.0%

Varies with storage conditions

Flake Size

3–20 mm

Depends on manufacturer processing

Acetone

Easily soluble (most commonly used)

Methylethyl ketone (MEK)

Good solubility

Ethyl acetate / ethanol mixtures

Soluble or partially soluble

Ethanol (pure)

Generally insoluble

Water

Insoluble, low hygroscopicity

Chloroform, dichloromethane

Soluble or swells

Thermal Decomposition Temperature

> 230°C

Weight Loss Range

230–350°C

Thermal Stability

Moderate; requires stabilizers or strict processing temperature control

Tensile Strength

40–60 MPa

Elongation at Break

10–20%

Flexural Modulus

1.5–2.5 GPa