ASTM-D-792比重測試

Changes in density of a single specimen may be due to
changes in crystallinity, loss of plasticizer, absorption of
solvent, or to other causes. Portions of a sample may differ in
density because of difference in crystallinity, thermal history,
porosity, and composition （types or proportions of resin,
plasticizer, pigment, or filler）.

關鍵詞:ASTM-D-792比重測試