P. R. Srinivasan

Bio: P. R. Srinivasan is an academic researcher from Indian Institute of Technology Madras. The author has contributed to research in topics: Polyamide & Maleimide. The author has an hindex of 5, co-authored 6 publications receiving 66 citations.

Preparation and properties of polyamides containing dibenzothiphenediyl and 5,5-dioxodibenzothiophenediyl units

Abstract: Several new polyamides (3a–d, 6a–d, 7a and 7b) containing dibenzothiophenediyl units were prepared by low temperature solution polycondensation of dibenzothiophenediamines (1a, b) with aromatic diacyl dichlorides (2a, b) or of aromatic diamines (5a, b) with dibenzothiophenediacyl dichlorides (4a, b). Some of the polymers were soluble in polar amide solvents or DMSO. All the polymers possess inherent viscosities in the range of 0,6 to 1 dl/g. Thermal stability and crystallinity were determined. The resulting polyamides were found to be much more stable than the corresponding polymers having open-chain linkages.

Aromatic polybenzimidazoles. Syntheses, properties, and applications

Abstract: Outstanding performance characteristics under unusual and demanding operating conditions are the hallmarks of a class of macromolecular compounds commonly referred to as polyheteroaromatics. The all-aromatic polybenzimidazoles, which rank among the leading representatives of this class, are the topic of the present article. Beginning with the early report of a successful synthesis of poly(1,4-phenylene-5,5′(6′)-bibenzimidazole-2,2′-diyl) from Carl Marvel's laboratory, a 20-years' span of worldwide research activities has until now provided a wealth of synthetic information in the field of aromatic benzimidazole polymers, which is critically surveyed. The problems involved in the conventional high-temperature processing technology are pointed out, and recent preparative developments permitting a two-stage “prepolymer” approach are reviewed. Structure-property relationships are treated in detail, with special attention paid to the problem of high-temperature stability and flame retardancy. A major section of the article presents a discussion of application and performance data in some of the more advanced segments of materials technology.

Recent developments in the synthesis, thermostability and liquid crystal properties of aromatic polyamides

Abstract: Wholly aromatic polyamides were developed and commercialised some decades ago, and since then a great deal of effort has been expended to try to improve in particular the processability of the early materials. Work has focussed on attempting to improve polymer solubility in organic solvents, and to reduce the melting point of materials, by synthesizing a variety of macromolecular backbones with many different types of substituents. The challenge has been to modify these polymers, while not causing adverse changes in the unique and useful physical properties of this group of polymers. This has led to the development of entirely novel synthetic strategies to allow, for example, the introduction of potentially reactive groups, and also to an interest in the potential lyotropic and thermotropic liquid crystalline properties of these polymers. This review describes the various synthetic methodologies which have emerged in recent years, and then summarises and categorises progress in the understanding of the structure-property relationships of the polymers produced. Properties such as solubility, thermostability, lytropism and thermotropism are highlighted.

Novel nitrogen-containing heterocyclic compound and organic electronic device using the same

Abstract: The present invention provides a novel nitrogen-containing heterocyclic derivative and an organic electronic device using the same The organic electronic device according to the present invention has excellent properties in terms of efficiency, driving voltage, and a life span