Cl. Swanson et al., SKIN AND LAYER FORMATION IN FILMS PREPARED FROM CARBOHYDRATES, POLY(ETHYLENE-CO-ACRYLIC ACID), AND POLYETHYLENE, Journal of applied polymer science, 49(10), 1993, pp. 1683-1693
Cornstarch, a canary dextrin, and a maltodextrin were compared in film
s blown from carbohydrates compounded with poly (ethylene-co-acrylic a
cid) (EAA), low-density polyethylene (LDPE), and aqueous ammonium hydr
oxide plasticizer. Dextrins or maltodextrins having dextrose equivalen
t values of one and greater caused dark-colored films with caramel odo
rs, probably due to Maillard reactions. Blown films with hydrophobic s
kins and water-sensitive cores were produced with the dextrinized carb
ohydrates, but not from natural cornstarch. Water sensitivity of films
containing the dextrinized carbohydrate was reduced by recycling the
films through.the blown film die. A mechanism for development of the s
kins is proposed, as is a method for preparing thin semipermeable memb
ranes. (C) 1993 John Wiley & Sons, Inc.