Synthesis and characterization of new cross-linked terpolymer systems containing silyl group

Abstract

A series of acrylic terpolymers containing silyl pendant groups was prepared by free radical cross-linking copolymerization. Me 3 Si, Et 3 Si and t-BuMe 2 Si together with cubane-1, 4-dicarboxylic acid (CDA) were covalently linked with 2-hydroxyethyl methacrylate (HEMA). The silyl-linked HEMA are abbreviated as TMSiEMA, TESiEMA and TBSiEMA respectively. Cubane-1, 4-dicarboxylic acid (CDA) linked to two HEMA group is the cross-linking agent (CA). Free radical cross-linking terpolymerization of the methyl methacrylate (MMA) and methacrylic acid (MAA) with two different molar ratios of organosilyl monomers and CA was carried out at 60-70 • C. The compositions of the cross-linked three-dimensional polymers were determined by FT-IR spectroscopy. The glass transition temperature (Tg) of the network polymers was determined calorimetrically. The Tg of network terpolymers increases with increasing of cross-linking degree. Equilibrium swelling studies were carried out in enzyme-free simulated gastric and intestinal fluids (SGF and SIF, respectively). The gels swelled more in SIF than in SGF. The swelling behaviour of the copolymers was dependent on the content of MAA groups and caused a decrease in gel swelling in pH 1 or an increase in gel swelling in pH 7.4. Based on the great difference in swelling ratio at pH 1 and 7.4 for P-1, P-6 and P-10 appear to be good candidates for colon-specific drug delivery.

Synthesis and evaluation of trimethylolpropane triacrylate crosslinked superabsorbent polymers for conserving water and fertilizers

“…This might have resulted in the reduction of swelling values to 208, 335, 904 g/g, respectively. At pH value >9.0 the swelling was drastically reduced to 124 g/g due to repulsive forces among carboxylate anion 47, 48…”

Novel Carriers for Oral Delivery of Hydrophobic Drugs

“…Attaching the organosilyl groups to macromolecular chains should lead to important modifications of polymer properties such as biocompatibility. Silicones, or silicon polymers, have a number of advantages for use in medical devices and drug-delivery systems [15,16]. Silicone's hydrophobicity makes it particularly suitable for the delivery of lipophilic drugs [17,18].…”

Synthesis and characterization of new monomer and polymers of hindered silyl styrene

“…The silyl group that we used in this work is a lipophile group; therefore, synthesis of silyl derivatives of polymers and co-polymers could be important for application in drug-delivery systems. The presence of silyl groups in drug-delivery systems improved the selectivity of drugs [17]. The selectivity of organosilicon compounds compared to oxygen is an important factor in some properties.…”