Poly(2-hydroxy-3-phenoxypropylacrylate, 4-hydroxybutyl acrylate, dibutyl maleate) membrane controlled clonidine zero-order release.

Poly(2-hydroxy-3-phenoxypropylacrylate, 4-hydroxybutyl acrylate, dibutyl maleate) membrane was synthesized by UV curing method in our laboratory for the first time. When above-mentioned monomers were in the weight ratio of 4:4:2, the membrane not only had perfect permeation property but also had excellent plasticity, so the membrane made from monomers in the ratio of 4:4:2 was chosen as an optimized membrane. The optimized membrane provided perfect linear permeation properties in clonidine transdermal drug delivery system. The permeation rate decreased in proportion to the thickness of membrane. When the concentrations of clonidine were in the range of 0.5-7.0mg/ml, the permeation rate was proportional to the square root of clonidine concentrations. The optimized membrane was characterized by FTIR, DSC and SEM.