CM: Chlorinated polyethylene rubber

General Properties

Short Name:

Name: 

CM

Chlorinated polyethylene rubber


Chlorinated polyethylene, abbreviated CM or CPE, is formed by the direct reaction of polyethylene with chlorine. The properties of the resulting rubber are dependent on the chlorine content and distribution. The typical chlorine content is between approx. 25% and 48%. Added stabilizers prevent elimination of the chlorine from the polymer.

Structural Formula


Properties

Glass Transition Temperature-25 to -5°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 Temperature320 to 340 / 465 to 480°C
Young's Modulus2 to 15 MPa
Coefficient of Linear Thermal Expansion175 to 200 *10-6/K
Specific Heat Capacity-
Thermal Conductivity0.11 to 0.13 W/(m*K)
Density1.08 to 1.27 g/cm³
MorphologyAmorphous rubber
General propertiesGood ozone and UV light resistance
ProcessingCross linking by means of peroxides with activators, radiation or by means of thiazoles
ApplicationsCable sheathings. Technical rubber products. Hoses for engines. Impact modifier for PVC

NETZSCH Measurement

InstrumentDSC 204 F1 Phoenix®
Sample Mass14.21 mg
Isothermal Phase5 min
Heating/Colling Rates10 K/min
CrucibleAl, pierced lid
AtmosphereN2 (40 ml/min)

Evaluation

As an entirely amorphous polymer, CM shows a Temperatura di transizione vetrosaLa transizione vetrosa è una delle più importanti proprietà chimico-fisiche dei materiali amorfi e semi-cristallini, come, ad esempio, vetri, metalli (amorfi), polimeri, ingredienti farmaceutici e alimentari e definisce l’intervallo di temperatura in cui le proprietà meccaniche die materiali variano da duro e fragile a più morbido, malleabile o gommoso.glass transition step at -11°C (midpoint, both heatings). The glass transition temperature determines the minimal application temperature* for rubber materials. Below the glass transition, the polymer loses elasticity and gets hard and brittle. The step height (Δcp) is evaluated as 0.49 J/(g.K) in both heatings.

* DIN 3761-15 - Rotary shaft lip type seals for automobils; test; determination of cold resistant of elastomers; differential-thermoanalysis (withdrawn)