| 摘要 |
PURPOSE:To obtain the subject foam which is used as sheets because they have fine closed cells, a low density and a high expansion rate by mixing water- containing starch, water-containing PVA resin, a nonionic surfactant, a thickener and an inorganic filler, then melting and foaming the mixture. CONSTITUTION:(A) A starch high polymer of 5 to 30wt.% water content such as raw starch or enzyme-modified starch, (B) a PVA resin of 5 to 30wt.% water content, preferably having 80 to 100 mole % saponification degree and 700 to 3,000 polymerization degree, (C) a nonionic surfactant, preferably polyoxyethylene alkylphenyl ether, in an amount of 2 to 5wt.% based on the composition weight, (D) a thickener in an amount of 0.05 to 5wt.%, (E) an inorganic filter such as talc or clay, preferably in an amount of 3 to 20wt.% are mixed, molten and foamed to give the objective foamed products. |
