| 摘要 |
There are disclosed additive compositions for polymer base materials, which additive compositions are comprised of blowing agent (direct gas or chemical blowing agent), thermoplastic polymer carrier for the chemical blowing agent and filler, wherein the thermoplastic polymer carrier has a melting point below the decomposition temperature of the chemical blowing agent. The chemical blowing agent can be selected from those based on hydrazine, hydrazide, or azodicarbonamide, or those based on combinations of sodium citrate/citric acid and sodium bicarbonate. The filler can be selected from calcium carbonate, zeolites, clay and other known fillers. The polymer base sheet material can be, e.g., polyethylene, polypropylene, polybutylene, poly (p-phenylene oxide), polystyrene and combinations thereof. If direct gas blowing agent is used, then the compositions should contain a nucleating agent which may or not be the same as the chemical blowing agent. |
