Binary blends of poly(vinyl chloride) stabilized by lithium acetate-thermal studies

Abstract

A series of blends of poly(vinyl chloride) (PVC) with (1) poly(methyl methacrylate) (PMMA) or (2) polyoxymethylene (POM), with lithium acetate as a stabilizing agent, was investigated by differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA), either alone or coupled with Fourier transform infrared (FTIR) spectroscopy. It was found that lithium acetate has a significant effect on the thermal properties of blends under investigation. It causes the initial decomposition temperatures to increase by about 60 -150°C for PVC-POM blends, a substantial suppression of the volatile products evolution for PVC/PMMA blends, and an improvement in the surface morphology for both polymer systems by lowering the degree of roughness. The origin of these effects was discussed by analysis of the intermolecular complexation between metal salt and PVC structural arrangements in the blends. Such interactions may lead to the formation of long-range, directional-specific structural regularities, which in turn thermally stabilize the whole system (strong interactions model).

Preparation and characterization of PVC/montmorillonite nanocomposites—A review

“…The best overall performance, especially in flexural strength and in the heat deflection temperature (HDT), was displayed by samples containing 5% of NaMMT and 10% of PMMA. The organic modifier of MMT decomposed during the processing and accelerated the PVC degradation, but PMMA was able to reduce this negative effect [121,122].…”

Anhydrous Lithium Acetate Polymorphs and Its Hydrates: Three-Dimensional Coordination Polymers

“…Lithium acetate (hereafter referred to as LiC 2 ) is a very common salt of great importance due to its many and varied uses, such as (a) product for drug formulation and therapy, − (b) buffer for gel electrophoresis of DNA and RNA, (c) additive or catalyst for textiles and polymer production, , (d) precursor material for batteries − and ferromagnetic nanoparticles, (e) product for efficient yeast transformation, − lithium-6 CP/MAS standard, solvent, catalyst, etc. In this study, we describe LiC 2 and some of its hydrates forming different three-dimensional (3D) microporous frameworks.…”

Production and Properties of PVC–PMMA Binary Systems. A Review

“…The methods of thermogravimetric analysis (TGA) and IR spectroscopy were used to study a PVC-PMMA binary system stabilised with lithium acetate (ref. 34). It was established that the salt raises the temperature of the start of breakdown, suppresses the release of volatiles, and forms an intermolecular complex with PVC.…”