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The film cast from a small quantity of poly(vinyl alcohol)
having strong film forming property and a large quantity of
starch or it''s derivatives under the glycerol plasticizer, are
rapid effective biodegradability. And these films are impre-
ganated with water resistant resin, because of water soluble
film. Poly(vinyl alcohol) filled with starch or it''s
derivatives , generally will decrease mechanical properties,
and starch graft copolymer affact little than starch. When
glycerol is added with an increased quantity, the tensile
strength will decrease but elongation increase. In the flexible
blend polymer formed under the fixed com- position of poly(
vinyl alcohol ) and glycerol, less quantity of filler will
decrease mechancial properties and the opposite will increase
tensile strength but will continue to decrease elongation. In
the same large quantity of total starch, increase starch
graft copolymer will decrease tensile strength but will
increase elongation. Under the same quantity of filler, when
high graft percent one is used,the transparency will be lower,
and increase filler will decrease transparency more or less.
Impregnated water resistant film, in general, will show a
higher transparency. Increasing filler in the fixed
composition of poly( vinyl alcohol) and glycerol,will increase
water absorption,and lower graft percent one, in general, will
show a lower. And in the same large quantity of filler,
higher graft percent one will show a lower water absorption.
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