PolySciTech (www.polyscitech.com)
now provides trimethylene carbonate monomer (Polyvivo
AM05) with no minimum order required. This monomer can be utilized to
generate a variety of poly(trimethylene carbonates) and related
derivatives. Recent research has shown
that these polymers are primarily degraded via enzymatic routes. Zhang, Zheng, Roel Kuijer, Sjoerd K.
Bulstra, Dirk W. Grijpma, and Jan Feijen. "The in vivo and in vitro
degradation behavior of poly (trimethylene carbonate)."Biomaterials 27,
no. 9 (2006): 1741-1748. http://www.sciencedirect.com/science/article/pii/S0142961205008616
“Abstract: The in vivo and in vitro degradation behavior of
poly(trimethylene carbonate) (PTMC) polymers with number average molecular
weights of 69×103, 89×103, 291×103 and 457×103 g/mol (respectively abbreviated
as PTMC69, PTMC89, PTMC291 and PTMC457) was investigated in detail. PTMC rods
(3 mm in diameter and 4 mm in length) implanted in the femur and tibia of
rabbits degraded by surface erosion. The mass loss of high molecular weight PTMC457
specimens was 60 wt% in 8 wks, whereas the mass loss of the lower molecular
weight PTMC89 specimens in the same period was 3 times lower. PTMC discs of
different molecular weights immersed in lipase solutions (lipase from
Thermomyces lanuginosus) degraded by surface erosion as well. The mass and
thickness of high molecular weight PTMC291 discs decreased linearly in time
with an erosion rate of 6.7 μm/d. The erosion rate of the lower molecular
weight PTMC69 specimens was only 1.4 μm/d. It is suggested that the more
hydrophilic surface of the PTMC69 specimens prevents the enzyme from acquiring
a (hyper)active conformation. When PTMC discs were immersed in media varying in
pH from 1 to 13, the non-enzymatic hydrolysis was extremely slow for both the high
and low molecular weight samples. It can be concluded that enzymatic
degradation plays an important role in the surface erosion of PTMC in vivo.”
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