Showing papers in "Polymer Degradation and Stability in 2003"

TL;DR: The role of life cycle assessment (LCA) is discussed in this paper, a tool used for measuring environmental sustainability and identifying environmental performance-improvement objectives, and an overview of applications of LCA to PLA production and how they are utilized.

TL;DR: In this paper, a detailed analysis of chemical modifications and structural changes in the cellulose and lignin of Populus tremula and Buxus sempervirens (a softwood), as a result of photodegradation in a Xenon test chamber, is presented.

TL;DR: In this article, the degradation of a commercial environmentally degradable polyethylene was investigated in two stages: first by abiotic oxidation in an air oven to simulate the effect of the compost environment and secondly in the presence of selected microorganisms.

TL;DR: In this article, the effect of lignin antioxidant properties in polypropylene on stabilisation behavior was investigated. But, the effect on the solubility of PP could not be measured directly; a morphological criterion (average dimension of Lignin aggregates in the blend) has been correlated to antioxidant activity.

TL;DR: Life cycle inventories of energy consumption and carbon dioxide emissions favor the former product over the latter, reflecting smaller inventories and higher production yields of soybean oil compared to glucose.

TL;DR: In this article, the thermal behavior of poly(methyl methacrylate) (PMMA) with average molecular weights of 996,000 and 350,000 g mol was investigated by thermogravimetric analysis in dynamic conditions at four different heating rates: 2, 5, 8 and 10 K min.

TL;DR: In this article, the chemical changes that take place during the aging of polyethylene sheared electrical cables, and the correlation of these changes with physical properties need experiments with accelerated aging assays.

TL;DR: In this article, low-density polyethylene (LDPE) samples containing TDPA pro-oxidant additives from EPI Inc. were submitted to an investigation aimed at evaluating their ultimate biodegradation (e.g., mineralization) in soil and mature compost incubation media.

TL;DR: In this article, the degradation of polyethylene films containing pro-oxidant has been studied at three temperatures that normally occur during composting conditions, including temperature, oxygen concentration, and molecular mass of the materials.

TL;DR: In this article, the effect of sorbitol on the inter-and intramolecular hydrogen bonds of the proteins was investigated in the presence of a plasticizer, and it was shown that the degradation process started at ca. 300°C with the formation of gas products such as CO 2 and NH 3, suggesting that the reaction mechanism included at the same time the scission of the C−N, C−NH, C(O)−NH and C−OH bonds.

TL;DR: In this paper, the properties of blends of polycaprolactone and starch (PCL/starch) and maleic anhydride (MAH)-grafted-polycaprolacticone and starch were examined using Fourier transform infrared (FTIR) spectroscopy, 1H nuclear magnetic resonance (1H NMR), differential scanning calorimetry (DSC), and mechanical testing.

TL;DR: In this paper, the effects of fillers (talc and calcium carbonate) on polypropylene /ammonium polyphosphate/polyamide-6 (PP/APP/PA-6) intumescent system by using mechanical testing, LOI method, cone calorimetry and thermoanalytical techniques.

TL;DR: Injection molded tensile bars composed of native corn starch (0-70%), poly( d, l -lactic acid) (95% L) (PLA, 13-100%) and poly(hydroxyester-ether) (PHEE, 0-27%) were buried in soil for 1 year in order to study the effects of starch and PHEE on rates of biodegradation Rates of weight loss increased in the order pure PLA (∼0%/year) as mentioned in this paper.

TL;DR: In this article, the effects of different types of expandable graphite (EG) with magnesium hydroxide (MH) in halogen-free flame-retardant (HFFR) ethylene vinyl acetate (EVA) blends have been studied by cone calorimeter test (CCT), thermogravimetric analysis (TGA), limiting oxygen index (LOI), and UL-94 test.

TL;DR: Aliphatic homopolyesters are seemingly very similar with regard to their chemical structure and reactivity of the ester bonds, but their enzymatic degradation rates still differ significantly even at the same ΔTmt, which has obviously to be attributed to small changes in the chemical structure.

TL;DR: In this paper, the authors used thermogravimetric analysis (TGA) coupled with Fourier transform infrared (FTIR) spectroscopy to study polyamide 6 (PA6) and PA6-clay nanocomposites.

TL;DR: In this paper, the authors investigated how the crystalline structure of cellulose in cotton linters changed during soda, sulfate and organosolve pulping processes by using X-ray diffraction and FT-IR spectroscopy.

TL;DR: In this paper, the thermal and combustion behavior of an intumescent fire retardant system based on polyamide 6 and ammonium polyphosphate (APP), used to improve flame retardant properties of poly(ethylene-co-vinyl acetate) (EVA), loaded with Mg(OH) 2 (MH) was examined.

TL;DR: In this paper, Lignin has been investigated as flame retardant for isotactic polypropylene (PP) by means of thermogravimetric analysis in nitrogen and cone calorimetry with incident heat flux exposure.

TL;DR: In situ polymerized montmorillonite/polyamide 6 nanocomposites significantly degraded, producing a four-fold increase in e-caprolactam (monomer) content and a significant reduction in number average molecular mass as discussed by the authors.

TL;DR: In this article, it was shown that the rate of methanolysis strongly depends on the solubility of polyethylene terephthalate (PET) and that the depolymerization took place at random positions on the polymer chain.

TL;DR: In this article, a UV photo-oxidative degradation study on polyethylene/montmorillonite (PE/MMT) nanocomposite was carried out by FT-IR technique.

TL;DR: In this paper, X-ray diffraction and transmission electron microscopy were used to characterize the nano-structure of these composites while thermal stability was evaluated from thermogravimetric analysis and the flammability parameters using cone calorimetry.

TL;DR: In this paper, thermal degradation behavior and kinetic analysis of epoxy/montmorillonite nanocomposites were investigated by using a dynamic rate mode of a high-resolution thermogravimetric analyser (TGA).

TL;DR: In this paper, the effects of residual residual Sn on PLLA pyrolysis were investigated and three possible mechanisms of the zero-order weight loss were put forward as being possible mechanisms: an unzipping reaction accompanying a random transesterification, the other two being the Sn-catalyzed pseudoselective and selective lactide elimination reactions from random positions on a polymer chain.

TL;DR: In this paper, the photochemical behavior of polypropylene-clay nanocomposites was studied and the presence of stabilisers in the formulation has also been analyzed from the comparison of the rates of oxidation of stabilised and non-stabilised nanocompositionites.

TL;DR: In this paper, the thermal decomposition behavior of poly(propylene carbonate)s (PPC)s synthesized with varying molecular weights was studied at various pyrolysis temperatures by the combination of pyrolysgas chromatography/mass spectrometry (Py-GC/MS) and thermogravimetric analysis/infrared spectrometers (TG/IR) techniques.

TL;DR: Zinc hydroxystannate (ZHS) is found to be an effective partial replacement for the conventional hydrated fire-retardant fillers alumina trihydrate (ATH) and magnesium hydroxide (MH) when incorporated into a halogen-free EVA cable compound as mentioned in this paper.

TL;DR: In this paper, two different methods were used to prepare polypropylene/clay nanocomposites: pristine montmorillonite and a reactive compatibilizer hexadecyl trimethyl ammonium bromide (C6).

TL;DR: The potential and limitations of oven ageing tests, oxygen uptake measurements, differential scanning calorimetry (DSC) and chemiluminescence (CL) in stabiliser testing are reviewed in this article.