title: In situ formation of blends by photopolymerization of poly(ethylene glycol) dimethacrylate and polylactide.
abstract: Blends of cross-linked poly(ethylene glycol) dimethacrylate (PEGDMA) and poly(d,l-lactide) (PLA) were prepared by mixing photoactive PEGDMA (molecular mass: 875 g/mol) and PLA, and subsequently photopolymerizing the mixture with visible light. The effects of PLA molecular mass and mass fraction on the rheological properties of the PEGDMA/PLA mixtures, and on the degree of methacrylate vinyl conversion (DC), as well as blend miscibility, microstructure, mechanical properties, in vitro swelling behavior, and cell responses were studied. PLA-2K (molecular mass: 2096 g/mol) and PLA-63K (molecular mass: 63 000 g/mol) formed miscible and partially miscible blends with cross-linked PEGDMA, respectively. The addition of the PLA-2K did not affect the immediate or post-cure (>24 h) DC of the PEGDMA upon photopolymerization. However, the addition of PLA-63K decreased the immediate DC of the PEGDMA, which can be increased through extending the curing time or post-curing period. Compared to the cross-linked neat PEGDMA and PLA-2K/PEGDMA blends, PLA-63K/PEGDMA blends were significantly stronger, stiffer, and tougher. Both types of blends and the cross-linked PEGDMA swelled when soaked in a phosphate buffered saline (PBS) solution. The attachment and spreading of MCT3-E1 cells increased with increasing PLA-63K content in the blends. The facile and rapid formation of PEGDMA/PLA blends by photopolymerization represents a simple and efficient approach to a class of biomaterials with a broad spectrum of properties.
authors.affiliation: Polymers Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8543, USA.
authors.forename: Kai
authors.initials: K
authors.lastname: Zhang
authors.forename: Carl G
authors.initials: CG
authors.lastname: Simon
authors.forename: Newell R
authors.initials: NR
authors.lastname: Washburn
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Antonucci
authors.forename: Sheng
authors.initials: S
authors.lastname: Lin-Gibson
mesh_terms: D000179:Acrylates / Q000138:chemical synthesis* / Q000494:pharmacology; D000818:Animals; D002478:Cells, Cultured; D051379:Mice; D010775:Photic Stimulation / Q000379:methods*; D011091:Polyesters / Q000138:chemical synthesis* / Q000494:pharmacology; D011092:Polyethylene Glycols / Q000138:chemical synthesis* / Q000494:pharmacology / Q000528:radiation effects; D011108:Polymers / Q000138:chemical synthesis* / Q000494:pharmacology / Q000528:radiation effects; D013718:Tensile Strength / Q000187:drug effects / Q000528:radiation effects
chemical_list: D000179:Acrylates; D011091:Polyesters; D011108:Polymers; D011092:Polyethylene Glycols; C033616:poly(lactide); C035956:methyl acrylate