ARTICLE
degradation behavior of the various original polymers and
DACA-polymers was investigated by heating from 60 to 500
polymers were maintained after the terminal conjugation of
DACA and all of the DACA-polymers showed photoreactivities
corresponding to DACA units. DACA-polymers may be useful
as photoreactive PLLA, PDLLA, PCL, and PEG with high ther-
mal stability for biomedical and environmental applications.
ꢁ1
ꢀC at a rate of 20 C min under a nitrogen atmosphere at
a flow rate of about 250 mL minꢁ1. The heat resistance to
pyrolytic measurements of representative original PLLA and
DACA-PLLA were perfꢁo1rmed from 100 to 200 ꢀC oꢀr 240 ꢀC
ꢀ
This research was supported by the Osaka University 21st Cen-
tury COE Program ‘‘Center for Integrated Cell and Tissue Regu-
lation.’’ The authors acknowledge H. Uyama of the Department
of Applied Chemistry, Graduate of Engineering, Osaka Univer-
sity, for the TGA measurements.
ꢀ
at a rate of 20 C min , plus a hold at 200 or 240 C for 90
min under a nitrogen atmosphere at a flow rate of ca. 250
mL minꢁ1. The gas evolved from the original PLLA and
DACA-PLLA was investigated by pyrolysis at 250 ꢀC for
30 min, and then analyzed further by mass spectrometry.
Tin Quantification
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HIGH THERMAL STABILITY OF COMMERCIAL POLYESTERS, THI ET AL.
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