VARIATIONS IN PHYSICAL-CHEMICAL PROPERTIES OF BLOCK-COPOLYMER CHITOSAN WITH METHYL ACRYLATE DURING BIODEGRADATION UNDER THE ACTION OF ASPERGILLUS TERREUS - Biochemistry and Biotechnology: Research and Development - page 122

Table 1. Averaged temperatures of physical transitions in crab chitosan, CHS MA block-copolymer, and CHS/PMA mixture
before and after the action of Aspergillus terreus

tvap
(Н2О)
оС

Loss of mass with
respect to dry ,
mass%

Н2О,
mass%

ttr,
оС

tg(PMA)
оС

tg1,
оС

tg2,
оС

tdest1,
оС

tdest2,
оС

t ,
оС

Specimen m, g

302
(exo. max.)

328
(exo. max.)

Crab Chitosan initial 0.2446 8.9 132 ---- ---- 48 73.5 120.5 41

300
(exo. max.)

325
(exo. max.)

CHS MA block-
copolymer

0.5010 4.4 130 ---- 15 31 72 125 16

5.5
10.7
14.0

295
(exo. max.)

328
(exo. max.)

CHS PMA mixture*,
(through solution)

0.3247 6.7 130.5 ---- ---- 71.5 120 26

CHS MA copolymer
treated with
Aspergillus terreus
on the lawn

323
(endo. min)

342
(endo. min)

0.3002 5.2 120.5 13.5 25.5 61 102 47

19.5

CHS MA copolymer
treated with
Aspergillus terreus
under the lawn

324
(endo. min)

335.5
(endo. min)

0.2705 6.8 124 13 31 55 117 42

18

*)The dependence of t g (PMA) on the concentration of adsorbed water in the specimen, mass%: 14.0 (0); 10.7 (1.4); 5.5 (5.3)