Poly(glycidyl methacrylate) (PGMA)

Molecular Weight: Mw = 40,000 ~ 80,000Complete Physical & Thermal Property Data

1. Basic Information

• Full Name: Poly(glycidyl methacrylate), PGMA

• Repeating Unit Formula: C₇H₁₀O₃

• Monomer Molecular Weight: 142.15 g/mol

• Appearance: White ultrafine free-flowing powder

• Molecular Weight Range: Mw 40,000 – 80,000

• Polydispersity Index (PDI): 1.6 ~ 2.4 (conventional free radical polymerization); 1.2 ~ 1.5 (controlled radical polymerization)

• Structure Feature: Fully amorphous linear homopolymer with pendant epoxy groups

2. Thermal Properties

1. Glass Transition Temperature (Tg): 83 ~ 94 °C

• Mw 40,000: 82 ~ 86 °C

• Mw 60,000: 86 ~ 91 °C

• Mw 80,000: 90 ~ 95 °C

• Standard marked value: 85 ± 5 °C (tested by DSC, 10 °C/min heating rate, ASTM D3418)

2. Melting Point (Tm): No melting peak detectedPGMA is completely amorphous; no crystalline structure forms, so no melting point exists. Only viscous flow occurs above Tg.

3. Viscous Flow Processing Window: 120 ~ 210 °C

4. Thermal Decomposition Temperature (Td, 5% weight loss under N₂): ≥ 250 °C

• Slow degradation above 240 °C

• Severe thermal decomposition & self-crosslinking of epoxy groups above 280 °C

5. Coefficient of Linear Thermal Expansion: 7.2 × 10⁻⁵ ~ 8.5 × 10⁻⁵ K⁻¹

3. Physical & Mechanical Properties

1. Density (25 °C, compacted powder): 1.22 ~ 1.26 g/cm³

2. Refractive Index (nᴰ²⁰): 1.520 ~ 1.535

3. Tensile Strength (cast film): 62 ~ 70 MPa

4. Young’s Modulus: 3.2 ~ 3.6 GPa

5. Elongation at Break: 2.5 ~ 5.0 % (rigid & brittle polymer)

6. Rockwell Hardness: M82 ~ M88

4. Rheological Properties

1. Mark-Houwink Equation (THF, 30 °C): [η] = 1.12×10⁻⁴ × Mw⁰·⁷¹

2. Melt Viscosity at 200 °C

• Mw 40,000: ~3500 Pa·s

• Mw 80,000: ~18000 Pa·s

3. Flow Characteristic: Moderate melt fluidity; higher molecular weight leads to significantly increased viscosity

5. Solubility

• Soluble: Tetrahydrofuran (THF), acetone, DMF, dichloromethane and other polar organic solvents

• Insoluble: Water, ethanol, aliphatic hydrocarbons, mineral oil

6. Chemical & Epoxy Functional Properties

1. Theoretical Epoxy Equivalent Weight: 142 g/eq

2. Industrial Epoxy Value: 0.68 ~ 0.72 eq/100 g

3. Reactive Groups: Pendant oxirane (epoxy) rings

4. Crosslinking Reactions: Reacts with primary amines, secondary amines, thiols, carboxylic acids under mild heating or room temperature

5. Chemical Resistance: Resistant to weak acid, weak alkali and mineral oil; swelling occurs in strong polar aprotic solvents

7. Product Feature Summary (Marketing Version)

Poly(glycidyl methacrylate) with Mw 40,000–80,000 balances good film-forming performance, moderate melt fluidity and high epoxy reactivity. It avoids low-molecular-weight migration while retaining sufficient reactive sites for crosslinking. Suitable for coating additives, adhesive modifiers, powder coating curing agents and polymer compatibilizers.

Standard Short Description for Catalog

PGMA, white amorphous powder, Mw 40,000–80,000, Tg 85±5°C, no melting point, soluble in ketones and ethers, carrying high-activity epoxy side chains for crosslink modification. Stable below 220 °C for thermal processing.