| abstract |
Multi-layered, coinjection stretch blow moldedncontainers are obtained by stretch-blow molding a preformnprepared by coinjection-molding a polyester resin and an EVOHnresin mixture. Even though not having an adhesive resin layer,nthe containers have good impact delamination resistance andngood gas-barrier properties. Their transparency is high, andnthe resin melts for them are stable. The containers comprisena thermoplastic polyester layer (layer a) and a resinncomposition layer (layer b) of a mixture of two ethylene-vinylnalcohol copolymers (b1, b2) with the layer a being kept inndirect contact with the both surfaces of the layer b, whereinnthe dispersion morphology of the resin composition is such thatnthe particles of the ethylene-vinyl alcohol copolymer (b2)nhaving an ethylene content of from 35 to 48 mol% and a degreenof saponification of from 92 to 99 % are dispersed in the matrixnof the ethylene-vinyl alcohol copolymer (b1) having an ethylenencontent of from 25 to 40 mol% and a degree of saponificationnof at least 99 %, the resin composition gives at least two peaksnfor crystal fusion in its differential scanning calorimetryn(DSC), the difference between bl and b2 in the ethylene contentnfalls between 8 and 23 mol%, the difference therebetween innthe degree of saponification falls between 1 and 8 %, and thenblend ratio of b1 to b2 falls between 60/40 and 90/10. |