2003 |
Mechanical
Behaviour and Biocompatibility of Poly(1-Vinyl-2-Pyrrolidinone)-Gelatin IPN
Hydrogels
Lopes CMA, Felisberti MI
BIOMATERIALS
24 (7): 1279-1284 MAR 2003
Abstract:
IPN hydrogels based on poly(1-vinyl-2-pyrrolidinone) and gelatin were obtained
by casting of aqueous solution using potassium persulphate and glutaraldehyde as
respective crosslinking agents. Studies of swelling and mechanical behaviour
showed that the samples of different composition can incorporate high content of
water and still exhibit high compression strength. The composition has influence
at the global crosslinking density what affects the mechanical performance. In
vitro biocompatibility and hemocompatibility were also investigated. The
materials do not interfere on the cellular functions and neither induce platelet
adhesion. From this preliminary evaluation, it is possible to conclude that
these hydrogels have potential for applications in the biomedical field.
Blends of
i-PP and SBS. II. Influence of in situ Compatibilization on the Mechanical
Properties
Wilhelm HM, Felisberti MI
JOURNAL OF APPLIED POLYMER SCIENCE
87 (3): 516-522 JAN 18 2003
Abstract:
This article concerns the in situ compatibilization of immiscible isotatic
polypropylene/ styrene-butadiene-styrene triblock copolymer blends (i-PP/SBS) by
use of a reactive mixture. For this purpose, maleated PP (PP-MAH) and SBS (SBS-MAH)
were used as functionalized polymers and 4,4'-diaminediphenylmethane was used as
a coupling agent between maleated polymers, resulting in a graft copolymer.
Binary blends of i-PP/SBS, nonreactive ternary blends of i-PP/PP-MAH/SBS, and
reactive ternary blends of i-PP/PP-MAH/SBS-MAH with varying diamine/anhydride
molar ratios were prepared. The mechanical properties of the blends were
determined by tensile and impact-resistance tests. The optimum improvement in
the mechanical properties was found when the diamine/anhydride molar ratio in
the ternary reactive blends was 0.5/1. (C) 2002 Wiley Periodicals, Inc.