ISSN:
1436-2449
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Summary Racemic lactide (D,L-lactide) was bulk-polymerized comparatively using stannous octoate and zinc metal as initiators. A two-level fractional factorial design was used to assess the influence of selected experimental variables with respect to intermolecular transesterification, whose extent in the resulting high molecular weight poly(D,L-lactide)s (PLA50) was investigated by13C NMR. Five variables, namely polymerization temperature, monomer-to-initiator ratio, polymerization time, nature of the initiator and monomer degassing-time, were found significant and were ranked according to their average effect on transesterification. A significant interaction of polymerization temperature and polymerization time was also detected. Zinc led to lower stereoregularity than stannous octoate.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00973910
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