| 摘要 |
PURPOSE:To improve the gas barrier property and moldability of material by a method wherein saturated polyester and modified saponified ethylene-vinyl acetate copolymer, which contains pyrrolidone-ring-containing unit and ethylene unit, are injection-molded together and the resultant parison is stretch-blow- molded. CONSTITUTION:As thermoplastic saturated polyester (PES), PES, the major component of which is ethylene terephthalate, is preferably employed. The preferable content of ethylene unit in modified EVOH and unmodified EVOH mixed in the modified EVOH is within the range of 20-60 % by mol. In addition, the modified EVOH must contain 0.1-10 % by mol of pyrrolidone-ring- containing unit. The favorable degree of saponification of the modified EVOH and unmodified EVOH mixed in the denatured EVOH is 9 % by mold or more. The modified EVOH and PES under the above-mentioned state are injection- molded in multilayer. In this case, the constitution of layers is the configuration, in which the moldified EVOH is pinched between PESs, such as PES/modified EVOH/PES. The multilayer injected parison is subjected to stretch blow molding under the stretching temperature, which is set to be 75-150 deg.C. |
