SB: Styrene/Polybutadiene copolymer

General Properties

Short Name:

Name:

Styrene/Polybutadiene copolymer

SB is a copolymer from styrene and butadiene (and sometimes additional components), in which the individual monomers are lined up either in block form (block copolymer) or one monomer is grafted on the main chain of the second monomer (graft copolymer).

Structural Formula

Properties

Glass Transition TemperatureThe 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 Temperature	-90 to -50 / 80 to 110°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 reactionA decomposition reaction is a thermally induced reaction of a chemical compound forming solid and/or gaseous products. Decomposition Temperature	440 to 455°C
Young's Modulus	1800 to 2500 MPa
Coefficient of Linear Thermal Expansion (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	70 *10^-6/K
Specific Heat Capacity	1.2 to 1.3 J/(g*K)
Thermal ConductivityThermal conductivity (λ with the unit W/(m•K)) describes the transport of energy – in the form of heat – through a body of mass as the result of a temperature gradient (see fig. 1). According to the second law of thermodynamics, heat always flows in the direction of the lower temperature.Thermal Conductivity	0.17 to 0.18 W/(m*K)
DensityThe mass density is defined as the ratio between mass and volume. Density	1.05 g/cm³
Morphology	Amorphous thermoplastic
General properties	High transparency, high toughness and stiffness
Processing	Injection molding, extrusion, deep drawing
Applications	Packaging, toys

NETZSCH Measurement

Instrument	DSC 204 `F1` `Phoenix^®`
Sample Mass	12.17 mg
IsothermalTests at controlled and constant temperature are called isothermal.Isothermal Phases	5 min
Heating/Colling Rates	10 K/min
Crucible	Al, pierced lid
Atmosphere	N₂ (40 ml/min)

Evaluation

Both for block and graft copolymers, the characteristic properties of the monomers are largely retained so that SB has two Glass Transition TemperatureThe 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 transitions. The Glass Transition TemperatureThe 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 in the low-temperature range (here in both heatings at -84°C, midpoint) is due to the butadiene component. The Glass Transition TemperatureThe 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 98°C (2^nd heating, red, midpoint) is due to the styrene component. The irreversible effect in the 1^st heating (peak temperature 76°C) indicates the release of strong tensions in the material that are caused by the thermomechanical history of the polymer.