BIODEGRADABLE FILMS OBTAINED FROM CASSAVA STARCH AND THEIR MANUFACTURE PROCESS

摘要

The present invention is related to the elaboration of flexible films from cassaya starch for the manufacture of biodegradable packaging useful in the packing and packaging of dry foods and other products. The novel films of the invention are produced by extrusion of a mixture of cassaya starch and plasticizer.

主权项

1. A process for the production through extrusion of flexible biodegradable films, comprising the stages of:
(a) Milling and sieving in 50/bottom mesh the native or hydrolyzed cassaya starch with α-amylase obtained from Bacillus amyloliquefasciens. (b) Mixing the starch with glycerol as plasticizer agent and storing for 12-36 h at a temperature between 15 and 25° C. (c) Obtaining the [T1] thermoplastic starch (TPS) rod through extrusion of the mixture at a screw rate of 40 to 60 rpm with a temperature profile of 90-110/95-115/100-120/89-109° C. (d) Drying the TPS at a temperature between 40 and 50° C. during 12 to 36 h to obtain the TPS pellets. (e) Mixing PLA and PCL in the presence of maleic anhydride and benzoyl peroxide. (f) Obtaining the pellets from the binary blend [T2] through extrusion at a screw rate of 40 to 60 rpm with a temperature profile of 120-140/140-160/160-180/150-170° C. (g) Obtaining the flexible film through extrusion from the mixture of the TPS pellets and the binary blend at a screw rate of 40 to 60 rpm with a temperature profile of 110-130/125-145/155-175/135-155° C. [T1] rod [T2] binary blend