Authors:N. Ananthalakshmi, P. Wadgaonkar, S. Sivaram, and I. Varma
The paper describes the effect of molecular mass and copolymer composition on thermal behaviour of homopolymers and copolymers of glycidyl methacrylate and methyl methacrylate. The polymerisation was done by using group transfer polymerization (GTP) and free radical techniques. A multistep decomposition was observed in polymers prepared by free radical technique indicating the presence of weak linkages in the backbone. Copolymers prepared by GTP had fewer weak sites and degraded in single step by a random chain scission.
Authors:A. Ghanwat, M. Sayyed, P. Wadgaonkar, and N. Maldar
Aromatic polyamides find many applications in diverse and critical areas due to their high thermal stability coupled with
high mechanical properties. However most of such aramides are difficult to fabricate because of their limited solubility and
high melting temperature. Improvements in processability have been reported by incorporating bulky pendant groups and aliphatic
spacer groups. Similarly to improve the solubility of polymers approaches of incorporating silicon in main polymer chain and
co-polymerization techniques were useful. We report the synthesis and characterization of a series of phenylated silicon containing
aromatic–aliphatic polyamides from a mixture of 2, 5-bis (4-carboxy methylene phenyl)-3, 4-diphenyl thiophene (CMPDT) and
bis-(4-carboxy phenyl) dimethyl silane (BCPDS) in various mole proportions, with commercial aromatic diamine. Thus a series
of novel co-polyamides having pendant phenyl groups, methylene spacer and silicon moiety was prepared by judicious combination
of (CMPDT); BCPDS and aromatic diamine; bis-(4-aminophenyl) ether (ODA), by direct polycondensation using Yamazaki’s phosphorylation
method. These high molecular mass polyamides were obtained in high (89–98%) yields and had viscosities in the range of 0.23–0.57 dL/g
in DMAc. Polyamides showed improved solubility in polar aprotic solvents, like NMP, DMAc, DMSO and DMF; had high thermal stability;
with no mass loss below 335 °C.