Specific Gravity


Specific Gravity of Various Plastics

SPECIFIC GRAVITY- The ratio of the weight of the molded piece as compared to the weight of an equal volume of water ASTM D792.

Polybutylene 0.60

Polymethylpentene 0.83

Ethylene-propylene 0.86

Polypropylene 0.90-0.92


LDPE 0.91-0.93

LLDPE 0.91-0.94

HDPE 0.96-0.97

Polybutene 0.91-0.92

Natural rubber 0.91

Butyl rubber 0.92

Styrene-butadiene 0.93


PA-12 1.02 PA-11 1.04 PA-6 1.12-1.13 PA-66 1.13-1.15

ABS 1.04-1.07

Polystyrene 1.05

Polyacronitrile 1.17

Polyvinyl acetate 1.19

Polycarbonate 1.2

Polychloroprene rubber 1.23

Polysulphone 1.24

Polyethylene terephtalate 1.34-1.39

PVC 1.37-1.39

POM 1.41-1.43

Polytetrafluorethylene 2.27

Soon to follow:Simple examples of how to convert volume of your part from cubic cm or cubic inches to ounces and pounds per thousand parts.

Need to get back to my job for now. bye- you are leaving Specific-gravity, hope you visit injection mold tips again



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