M. Kayalvizhi

Polymeric drug based on acrylates for biological applications: synthesis, characterization, antimicrobial, and drug release study

Chalcone derivative and their polymers are synthesized, characterized, tested for their antimicrobial activity against four different micro-organisms. In vitro cumulative drug release studies are done using UV–visible spectroscopic technique. 2,4-Dichloro-1-ene(4-hydroxyphenyl)phenone (DHP) is synthesized using 4-hydroxy benzaldehyde and 2,4-dichloro acetophenone. 4-[3-(2,4-Dichloro-phenyl)3-oxoprop-1-en-1-yl]phenylacrylate (DCP) is prepared by reacting DHP with acryloyl chloride. Copolymer of DCP is prepared using acrylic acid and hydroxyl ethyl acrylate. The drugs are characterized by IR, 1H NMR, and UV–visible spectroscopic techniques. Molecular weight of the polymer is 4000 g/mol. First decomposition temperature of the polymers is around 320 °C. MIC value of the drug is very high for gram-negative bacteria (1.95 μg/mL). In vitro drug release rate is dependent on the comonomer, pH, and temperature.

Tri-Block Copolymer Based on Crystallizable Amide Segments and Functionalized Polystyrene

This article discusses the synthesis and characterization of segmented tri-block copolymers using monofunctional hard segments (mHS) and difunctional polystyrene soft segments. The main goal of this work was to modify high Tg polystyrene to semicrystalline material, thereby increasing the solvent resistance. Three hard segments were used. The soft segment molar mass was varied from 2500 to 10000 g/mol using dimethyl terephthalate (DMT) as a chain extender. The viscosity of the copolymer linearly increased with respect to the molecular weight of the SS. The crystallization behaviour of the copolymer was studied by DSC and FT-IR. The TGA results revealed that all copolymers had single-stage decomposition centred around 427 °C, and the solvent resistance of these materials was very high even at a low amide content. All the copolymers showed low water absorption.

Synthesis and characterization of polyurethane-urea-amide based on functionalized polystyrene

Hexamethylene diisocyanate (HMDI) based polyurethane-urea-amide (PUUA) is synthesized using diamide chain extenders and dihydroxy polystyrene. The rigid segment structure is HMDI-6X6-HMDI. The repeating molecular weight of the soft segment is varied from 2678 to 9202 g mol−1 using HMDI as a chain extender. The inherent viscosity of the polymer is 1.3–3.9 dL g−1. Tm of PUUA varies between 239 and 265 °C. The crystallinity of the amide segments is up to 70%. The polymers show single-stage decomposition temperature around 415 °C. WAXS data confirm the semi-crystalline nature of the polymer. The solvent resistivity of the polymer in chloroform is high due to high crystallinity of the hard segment.