POLYMER CLASS | Polyalkene (Polyolefin) |
COMMON NAMES | Poly(isobutene), Poly(isobutylene), Butyl rubber |
STRUCTURE BASED NAME | Poly(1,1-dimethylethylene), Poly(2-methylprop-1-ene) |
ACRONYMS | PIB |
CAS # | 9003-27-4 |
CurlySMILES | C{-}C{n+}(C)(C) |
CAS # | 68606-25-7 |
COMMON NAMES | Isobutene |
SMILES | CC(=C)C |
Std. InChI | 1S/C4H8/c1-4(2)3/h1H2,2-3H3 |
Std. InChIKey | VQTUBCCKSQIDNK-UHFFFAOYSA-N |
STRUCTURE |
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PROPERTY | UNIT | VALUE / RANGE | PREFERRED |
Molar Volume Vm | mL mol-1 | 61.4 - 66.8 | 63.8 |
Density ρ | g mL-1 | 0.84 - 0.91 | 0.88 |
Solubility Parameter δ | MPa1/2 | 14.4 - 17.7 | 15.8 |
Molar Cohesive Energy Ecoh | J mol-1 | 13400 - 20300 | 16300 |
Glass Transition Temperature Tg | K | 195 - 208, 243 | 202 |
Molar Heat Capacity Cp | J (mol K)-1 | 109.5 - 110.5 | 110 |
Entanglement Molecular Weight Me | g mol-1 | 5900 - 10500 | 7950 |
Index of Refraction n | none | 1.505 - 1.51 | 1.51 |
PROPERTY | UNIT | VALUE / RANGE | PREFERRED |
Molecular Weight of Repeat unit | g mol-1 | 56.11 | |
Van-der-Waals Volume VvW | mL mol-1 | 41.12 | |
Molar Volume Vm | mL mol-1 | 62.2 - 66.6 | 64.7 |
Density ρ | g mL-1 | 0.84 - 0.90 | 0.87 |
Solubility Parameter δ | MPa1/2 | 15.1 - 15.9 | 15.4 |
Molar Cohesive Energy Ecoh | J mol-1 | 14200 - 16500 | 15400 |
Glass Transition Temperature Tg | K | 199 - 202 | 201 |
Molar Heat Capacity Cp | J (mol K)-1 | 112 - 117 | 114 |
Entanglement Molecular Weight Me | g mol-1 | 6900 - 8200 | 7600 |
Index of Refraction n | none | 1.47 - 1.51 | 1.49 |
Last updated: December 10, 2019