Showing papers in "Polymer Degradation and Stability in 1981"

TL;DR: In this paper, the carbonyl profiles within naturally and artificially weathered low density polyethylene samples (3 mm thick) have been measured and found to exhibit the same characteristics.

TL;DR: In this paper, a first step in the thermal degradation of polystyrene prepared by radical polymerization has been isolated by heating the polymer in the temperature range 199-280°C.

TL;DR: In this article, it was found that the initial increase in light emission from pre-oxidised polypropylene, measured in a nitrogen atmosphere, is due to decomposition of hydroperoxides in the system.

TL;DR: In this article, the decay of the 1,4-polybutadiene absorbance (infra-red) was found to correlate with the decrease in tan δ at −80°C during the photo-and thermal oxidation of ABS.

TL;DR: In this paper, the surface photo-oxidation of polystyrene film is examined using ESCA and the initial stage involves the formation, primarily, of CO groups on the surface.

TL;DR: In this paper, the effect of two hindered piperidine compounds on the photo-stability and light stabilising performance of a 2-hydroxy-benzophenone and a 2hydroxybenzotriazole stabiliser in polypropylene film has been examined.

TL;DR: In this article, it was shown that the thermal behavior of a mixture of polypropylene and a fire retardant chlorinated paraffin (Cl 70%) is not the sum of their individual behaviours.

TL;DR: In this paper, a quantitative correlation was found between the rate of change of the ultimate tensile strength of polystyrene and the extent of thermal oxidation in the closed chamber of a Brabender Plastograph.

TL;DR: In this paper, it has been shown that the benzoylacetone can substitute allylic chlorine atoms through a C-alkylation reaction which takes place only in the presence of ZnCl2 as catalyst.

TL;DR: In this paper, it was shown that blends of low density polyethylene (LDPE) and polypropylene (PP) photo-oxidise more readily than LDPE alone and there was evidence of cross-link between the two phases.

TL;DR: In this paper, it was shown that a polymer reactive UV absorber (I) can be chemically combined with ABS in a redox reaction to give modified polymers containing up to 25g of bound UV stabiliser per 100 g of polymer.

TL;DR: In this paper, the melt rheology and long-term stability of unstabilised polypropylene are found to be grossly affected during reprocessing, and the most cost effective materials are the light stable transition metal sulphur complexes typified in the present work by the transition metal dithiocarbamates (II).

TL;DR: In this paper, a regenerative mechanism was proposed to explain the synergistic effect of organotin in mixed metal carboxylate stabilisers for polyvinyl chloride (PVC).

TL;DR: In this article, the effect of the mechano-chemical process on the efficiency of adduct formation and on the effectiveness of the stabilisers so formed is discussed, and the synergistic combinations of a bound antioxidant (BHBM (I(a)) and a bound uv stabiliser (EBHPT (II)) confer a high level of uv stability on ABS when incorporated into ABS.

TL;DR: In this article, the effect of two hindered piperidine compounds on the photo-sensitised oxidation of polypropylene by anthracene, anthraquinone, benzhydrol and benzophenone has been examined using infra-red, ultraviolet absorption luminescence and flash photolysis techniques.

TL;DR: In this article, the surface composition and structure of poly(methyl methacrylate) and nylon 66 have been studied after ultraviolet irradiation in oxygen (∼ 1 atm, 20°C).

TL;DR: In this article, the rates and mechanisms of the thermal degradation of nine alternating poly(olefin sulphone)s with different olefin structures were investigated at 150°C and 200°C by a novel technique which is particularly suitable for studying the initial steps of the degradation.

TL;DR: A rubber reactive antioxidant, 4-(mercapto acetamido)diphenylamine (I, MADA) was found to be more effective as an antiozonant when prereacted with the rubber chain than when present as a conventional compounding ingredient (MADA-A) at the same molar concentration.

TL;DR: In this article, the catalytic effect of various butyl-tin chlorides on the dehydrochlorination reaction of chlorohexene, used as a model compound for allylic chlorides in poly(vinyl chloride), has been studied in tetrahydrofuran and dichloroethane solutions.

TL;DR: In this article, the degree of polyacetal degradation depends on uv dose and temperature, and the effect of moisture on the photo-oxidative process is shown to be a function of site latitude.

TL;DR: In this article, Fourier transform infrared spectroscopy (FTIR) was used to examine the inhibited autoxidation of polybutadiene (BR) in the presence of three chain-breaking antioxidants.

TL;DR: In this article, evidence is presented which suggests that during high temperature processing of LDPE/PVC blends with limited air access, cross-phase chemical interaction occurs to give LP copolymers.

TL;DR: In this article, the authors examined phenolic sulphur compounds as antioxidants for polypropylene in oven-ageing studies and found that the activity was in the order sulphoxide > sulphide > sulphone.

TL;DR: In this article, the effect of destroying carbonyl and hydroperoxide groups in oxidised polypropylene on the subsequent rate of photo-oxidation has been examined using infra-red spectroscopy.

TL;DR: In this paper, the reaction ratios for 2-bromoethyl methacrylate (M1)/methyl acrylate copolymer (M2) were obtained using a nuclear magnetic resonance spectroscopic technique: r1 = 2.77 ± 0·03, r2 = 0.19 ± 0.02.

TL;DR: In this paper, the mass-flow balance during experiments carried out by heating samples near, but not on, the balance platform have been ascribed to pressure gradients developing around the platform.

TL;DR: In this article, the photolysis of polystyrene in solution and in films has been studied using radiation greater than 300 nm in the absence of oxygen, and it is proposed that the species responsible for initiation of the scission reaction is a molecular complex between polymer and solvent.