Polymer alloy sausage casings - contg. polymer with anhydride gps. and polymer contg. gps. which interact with hydrogen atmos. to form hydrogen bridges

摘要

Sausage casing material in which at least one layer is comprised of a high temp.-stable, homogeneous alloy of (a) one or more high molecular polymers with anhydride gps. and (b) one or more high molecular polymers contg. gps. which can interact with H atoms to form hydrogen bridges, the polymers (a) and (b) each having a mol. wt. of at least 10000. Component (a) is pref. a copolymer of an alkylenically unsatd. monomer with maleic anhydride, esp. a styrene/maleic anhydride copolymer. Component (b) is pref. a polymer contg. ester gps., such as a cellulose ester or a poly(meth)acrylate. Pref. the ratio component (b) to component (a) is 9:1 to 1:9, esp. 7:3 to 4:6. The moisture permeability of the layer may be controlled by converting the anhydride gps. in the copolymer into acid gps. and/or opt. substd. carbonamide gps. and/or ester gps. and/or aminoester gps. The copolymer may also be crosslinked. The alloy layer may contain a plasticiser such as triacetin and may be combined with one or more layers of natural material such as natural gut or collagen.S The polymer alloys give materials having properties very similar to those of natural sausage casing materials, and give improved filling performance and recovery after loading than prior art thermoplastic casing materials.