Pii: S0032-3861(00)00031-8
نویسندگان
چکیده
A model was developed to describe the overall dissolution kinetics of semicrystalline PVA gels prepared by freezing and thawing techniques. The dissolution process was described as a three-step mechanism: detachment-, diffusion-, and disentanglement-controlled dissolution. The unfolding of crystalline regions due to detachment and diffusion was calculated. The lamellar thickness of a PVA crystal was found to significantly change the rate of unfolding and thus, the overall dissolution kinetics. The model predicted the effect of the lamellar thickness, time of swelling, and sample thickness on the crystal chain unfolding and potential dissolution of freeze/thawed PVA hydrogels. q 2000 Elsevier Science Ltd. All rights reserved.
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