Rohacell® 31 Polymethacrylimide (PMI) Rigid Foam Sheet

Technical Documents

ROHACELL 31 is the lowest density grade and a very high strength:weight ratio.

Details

Product Type

Polymer > Polyimides

Applications

Polymers industry
Composites

Producer

Evonik

Supplier

Evonik Iran

Chemical Composition

ROHACELL is manufactured by hot forming of methacrylic acid/methacrylonitrile copolymer sheets. During foaming this copolymer is converted to polymethacrylimide.Information supplied by Emkay Plastics, Ltd.

Advantages
  • closed-cell rigid expanded plastic material for light weight sandwich construction
  • excellent mechanical properties
  • high dimensional stability under heat
  • solvent resistance
  • particularly at low temperature, a low thermal conductivity
  • highest strength and moduli values
  • highest for any foamed plastic in its density range

Technical data

Quantity Value Unit Comment
Appearance Properties
Appearance White
Physical Properties
Density 0.0320 g/ml ASTM D1622-63
Thermal Properties
Maximum Service Temperature 180 ºC Dimensional stability per DIN 53424; Air
Thermal Expansion 25.0 µm/m-°C Temperature -100 °C; Linear@
Thermal Expansion 37.0 µm/m-°C ASTM D696-70@Temperature 20.0 °C; Linear
Thermal Conductivity 0.0310 W/mk ASTM C177-63
Mechanical Properties
shear modulus 12.8 MPa ASTM C273-61
shear strength 0.393 MPa ASTM C273-61
Flexural strength 0.786 MPa ASTM D790-66; at Yield
Tensile strength 0.979 MPa ASTM D638-68;Ultimate
Compressive Strength 0.393 MPa ASTM D1621-64; at Yield
Elongation at break-MD 3.5 % ASTM D638-68
Tensile modulus-MD 35.3 MPa ASTM D638-68
Chemical Properties
Moisture absorption 1.5 % at Equilibrium;15% RH
Moisture absorption 4.7 % at Equilibrium; 50% RH
Moisture absorption 19.5 % at Equilibrium;98% RH
Moisture absorption 2.9 % at Equilibrium; 30% RH
Water absorption 13 % 50days immersion at 20°C; at Saturation
Moisture absorption 6.0 % at Equilibrium; 65% RH
Moisture Expansion <1.0 % 50days immersion at 20°C
Oxirane Oxygen Content 19 - 20 %
Electrical Properties
Dielectric Constant 1.06 Frequency 2.60e+10 Hz@
Dissipation Factor 0.00080 Frequency 1e+10 Hz@
Dissipation Factor 0.0034 Frequency 2.60e+10 Hz@
Surface Resistance 2.00e+13 ohm
Dissipation Factor 0.00040 Frequency 5.00e+9 Hz@
Dissipation Factor 0.00010 Frequency 2.00e+9 Hz@
Dielectric Constant 1.05 Frequency 5.00e+9 Hz@
Dielectric Constant 1.05 Frequency 1e+10 Hz@
Dielectric Constant 1.08 Frequency 2.00e+9 Hz@