Design of bioabsorbable, amorphous polymer networks and composites

Miscellaneous · Wed Jan 01 00:00:00 EST 1992

OSTI ID:7153129

Wiggins, J S

Amorphous, crosslinked, bioabsorbable polymers have been developed as an alternative to conventional linear, semi-crystalline thermoplastic bioabsorbable polymers, and as matrix resins for totally bioabsorbable composites. Bioabsorbable composites have been fabricated, consisting of poly(glycolic acid) surgical mesh embedded in polyester and polyester-urethane based matrices. Low-molecular weight precursors used in the matrices of the composites were based on D, L-lactide and [epsilon]-caprolactone polyols, which were synthesized by coordination ring-opening polymerization using glycol initiators and stannous octoate as catalyst. Polymers initiated with diols were chain extended with fumaric acid for use as unsaturated polyester prepolymers, and were crosslinked using peroxide initiation. Polyester triols synthesized from glycerol initiation were crosslinked with L-lysine diisocyanate (LDI). Networks synthesized from D, L-lactide based precursors were more rigid with higher tensile strengths and moduli, while networks synthesized from [epsilon]-caprolactone were more flexible and elastomeric. Copolymer network properties were influenced by the relative amounts of each monomer incorporated into the copolymers. A composite based on neat poly(D, L-lactide-co-[epsilon]-caprolactone) fumarate displayed a tensile strength of 37 MPa and modulus of 107 MPa; addition of 25 wt% styrene yielded tensile strength and modulus of 64 MPa and 689 MPa, respectively. A silane coupling agent was shown to dramatically improve the fiber-matrix interfacial adhesion; tensile strength of a poly(D, L-lactide-co-glycolic acid) fumarate composite was increased from 84 to 92 MPa upon fiber pretreatment. Improved adhesion was also demonstrated using SEM. DSC revealed that if the glass transitions for the matrices was maintained at [approximately]60[degrees]C, the composites were easily shaped above this temperature, yet remained rigid at biological temperatures.

• Research Organization: University of Southern Mississippi, Hattiesburg, MS (United States)
• OSTI ID: 7153129
• Resource Relation: Other Information: Thesis (Ph.D.)
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
BIOLOGICAL MATERIALS
ABSORPTION
ORGANIC POLYMERS
DESIGN
FABRICATION
AMORPHOUS STATE
GLYCOLIC ACID
MATRIX MATERIALS
MECHANICAL PROPERTIES
PHYSICAL PROPERTIES
POLYESTERS
POLYURETHANES
CARBOXYLIC ACIDS
ESTERS
HYDROXY ACIDS
MATERIALS
MONOCARBOXYLIC ACIDS
ORGANIC ACIDS
ORGANIC COMPOUNDS
PETROCHEMICALS
PETROLEUM PRODUCTS
PLASTICS
POLYAMIDES
POLYMERS
SORPTION
SYNTHETIC MATERIALS
360601* - Other Materials- Preparation & Manufacture
400201 - Chemical & Physicochemical Properties