Praful P. Shah

Synthesis and Characterization of the Poly-(2-Methoxycyanurate) of 1,1′-Bis-(4-Hydroxyphenyl)-cyclohexane

Abstract The poly-(2-methoxycyanurate) of l, l′-bis-(4-hydroxyphenyl)-cyclohexane (PMCBC) was synthesized by the interfacial poly-condensation technique. The polymer was fractionated by preparative gel permeation chromatography (GPC). The fractions were characterized by viscometry, osmometry, and GPC techniques. The viscosity-molecular weight relationship was established in pure solvent and in different binary solvent mixtures. The unperturbed dimensions, (〈R2〉0/M)1/2, and the solvent-polymer interaction parameter, B, were computed by applying the two-parameter theories of the excluded-volume effect.

Synthesis and characterization of poly-[2-methoxy-4,6-di(2,7-naphthyloxy)-s-triazine]

Abstract Poly[2-methoxy-4,6-di (2,7-naphthyloxy)-s-triazine] was synthesized by interfacial polycondensation of 2-methoxy-4,6-dichloro-s-triazine with 2,7-dihydroxy-naphthalene. The polymer was characterized by IR and UV spectra, dynamic mechanical analysis, differential scanning calorimetry, and thermogravimetric analysis. The polymer was fractionated by the fractional precipitation method and the fractions were characterized by viscometry and membrane osmometry. The polymer has a Tg of 175°C and is found to be stable up to 300°C in air. The polymer sample is found to degrade in air in two steps, and the energy of activation for the first step is around 25 kcal/mol.

Water insoluble polyacrylamide. V: Dilute solution properties of poly (N-acryloyl-o-aminobenzoic acid)

Abstract A high molecular weight poly( N -acryloyl- o -aminobenzoic acid) has been synthesized by radical polymerization in a mixed solvent medium. The polymer has been fractionated by fractional precipitation and the fractions characterized by viscometry, vapour pressure osmometry and gel permeation chromatography. Mark-Houwink-Kuhn-Sakurada relationships are developed for three solvents. The values of unperturbed dimensions, (〈 R 0 2 〉/ M ) 0.5 , are evaluated by application of two-parameter theories of the excluded volume effect, developed by Fixman, Kurata, Stockmayer and Roig and by Bueche and James and first order perturbation theory. Based on the value of the conformational parameter σ, the polymer is found to behave as a semiflexible polymer in solution as a result of the increased bulk of the lateral group.

Synthesis and characterization of new polyetheramides

Abstract Polyetheramides (PEAs) are prepared by polycondensation of N,N′-diacetyl-o-tolidide with Bisphenol A, C, or F, phenolphthalein, resorcinol, catechol, hydroquinone, or 1,5- or 2,7-dihydroxynaphthalene or ethylene, butylene, propylene, diethylene, or triethylene glycol. The fusible and soluble oligomers are characterized. An attempt is made to bring out the relationship between various properties of PEAs and their structures.

Synthesis and characterization of some new polyamidoethers

Abstract Polyamidoethers have been prepared by polycondensing N,N′-dichloroacetyl-o-dianisidine (DCAD) with five aliphatic diols and nine dihydroxyarenes respectively. These polyamidoethers have been characterized by i.r. spectroscopy, estimation of M n by vapour pressure osmometry and measurement of solution viscosity in DMF at 35°. Thermal behaviour of selected polyamidoether samples has been studied by TGA in air.

Evaluation and Interpretation of Ptitsyn-Eizner Parameter λ in Dilute Solutions of Poly[2-methoxy-4,6-di(p,p′-isopropylidene Diphenyloxy)-s-triazine] and Other Polymers with Aromatic Backbone

Abstract Dilute solution data on poly[2-methoxy-4,6-di-(p,p′-isopropyl-idene diphenyloxy)-s-triazine] have been analyzed by the Ptitsyn-Eizner theory. The rigidity parameter λ has been estimated. λ varies with the nature of the solvent. The temperature dependence of λ has also been investigated. The parameter λ has been compared with other polymers containing “long bonds.”