title: Control of pore size in L-lactide/epsilon-caprolactone copolymer foams for tissue regeneration by the freeze-drying method.
abstract: In the regeneration and repair of missing tissues, synthetic polymer scaffolds need many pores to involve cells and to supply cells with nutrients. The control of the pore size of biodegradable L-lactide/epsilon-caprolactone copolymer foams was studied by changing the polymer concentration and the cooling temperature in the freeze-drying method. The mixtures of polymer and 1, 4-dioxane solution were poured into an 18-8 stainless steel Petri dish and frozen. The pore size of a polymer foam tends to increase from the bottom towards the top of a Petri dish. The pore size decreased to one-half with increasing polymer concentration (1 to 10 wt%). The mean pore size in foams of 8% polymer concentration decreased from 100 microm to 20 microm as cooling temperature was lowered. This suggests that the higher cooling rate due to lower cooling temperature can produce smaller ice-crystals and result in smaller pores.
authors: Division of Biomaterials Science, Graduate School of Dentistry, Osaka University, 1-8 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors: Hiroyuki
authors: H
authors: Nakao
authors: Suong-Hyu
authors: SH
authors: Hyon
authors: Sadami
authors: S
authors: Tsutsumi
authors: Takuya
authors: T
authors: Matsumoto
authors: Junzo
authors: J
authors: Takahashi
mesh_terms: D020341:Absorbable Implants; D000704:Analysis of Variance; D003460:Crystallization; D004146:Dioxanes / Q000737:chemistry; D005612:Freeze Drying; D006801:Humans; D007053:Ice; D008422:Materials Testing; D011091:Polyesters / Q000737:chemistry*; D016062:Porosity; D018709:Statistics, Nonparametric; D013499:Surface Properties; D013997:Time Factors; D023822:Tissue Engineering / Q000295:instrumentation*
chemical_list: D004146:Dioxanes; D007053:Ice; D011091:Polyesters; C062968:lactide-caprolactone copolymer; C025223:1,4-dioxane