摘要 |
A process for making a film of butene-1 homopolymer and copolymers of improved strength and clarity and the film made thereby. Such a film is produced by quenching an extruded poly(butene-1) homopolymer or copolymer while in the amorphous state, preferably at temperatures below 0 DEG C., and biaxially stretching the quenched film before substantial crystallization occurs. Subsequent heat setting of the film at a temperature above the stretching temperature, but below its melting point, produces a heat stable film of high break strength and clarity, suitable as a food wrap or food container overwrapping material.
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