PIB: Polyisobutylene

General Properties

Short Name:

Name:

PIB

Polyisobutylene(C₈H₈)_n1 (C₄H₆)_n2 (C₃H₃N)_n3

Polyisobutylene (PIB) is the oldest, commercial olefin polimerizate and was launched in the 1930’s. Depending on the degree of polymerization and molar mass, PIB can have a viscous, plastically sticky or rubberlike consistency.

Structural Formula

Properties

Glass Transition Temperature	-70 to -60°C
Melting Temperatures and EnthalpiesThe enthalpy of fusion of a substance, also known as latent heat, is a measure of the energy input, typically heat, which is necessary to convert a substance from solid to liquid state. The melting point of a substance is the temperature at which it changes state from solid (crystalline) to liquid (isotropic melt).Melting Temperature	-
Melting Temperatures and EnthalpiesThe enthalpy of fusion of a substance, also known as latent heat, is a measure of the energy input, typically heat, which is necessary to convert a substance from solid to liquid state. The melting point of a substance is the temperature at which it changes state from solid (crystalline) to liquid (isotropic melt).Melting Enthalpy	-
Decomposition Temperature	390 to 400°C
Young's Modulus	-
Coefficient d'Expansion Thermique Linéaire (CLTE/CTE)The coefficient of linear thermal expansion (CLTE) describes the length change of a material as a function of the temperature.Coefficient of Linear Thermal Expansion	120 *10^-6/K
Specific Heat Capacity	1.97 J/(g*K)
Thermal Conductivity	0.12 to 0.20 W/(m*K)
Density	0.91 to 0.93 g/cm³
Morphology	Amorphous thermoplastic
General properties	High elongation at break, good electrical insulating properties, resistant to acids, bases and salts.
Processing	Extrusion, calendering.
Applications	Building industry, sealing compounds, component of coatings, adhesive, basic material for chewing gum, plastification of explosives.

NETZSCH Measurement

Instrument	DSC 204 `F1` `Phoenix^®`
Sample Mass	15.17 mg
Isothermal Phases	20 min/2 min/20 min
Heating/Colling Rates	10 K/min
Crucible	Al, pierced lid
Atmosphere	N₂ (40 ml/min)

Evaluation

PIB is an amorphous thermoplastic, as reflected in the DSC curves. In both heatings, a Température de Transition VitreuseThe glass transition is one of the most important properties of amorphous and semi-crystalline materials, e.g., inorganic glasses, amorphous metals, polymers, pharmaceuticals and food ingredients, etc., and describes the temperature region where the mechanical properties of the materials change from hard and brittle to more soft, deformable or rubbery.glass transition at -64°C (midpoint) was observed exclusively. The step heights (Δc_p) are identical in both curves and have a value of 0.39 J/(g·K) in both the 1^st heating (blue) and 2^nd heating (red).