When wood is exposed to elevated temperatures, changes can occur in its chemical structure that affect its performance. The extent of the changes depends on the temperature level and the length of time under exposure conditions. The changes in chemical structure may be manifested only as reduced strength, and hydroscopic water and volatile oil weight loss. In contrast, very drastic chemical cha...

the principal effects of mass degradation on polymer matrix composites (pmcs) are the decay of mechanical properties such as strength, elongation, and resilience. this degradation is a common problem of the pmcs under thermal cycling conditions. in this article, composite degradation was investigated by measurement of total mass loss (tml) using the taguchi approach. thermal cycling tests were ...

The thermal degradation behavior and pyrolysis kinetic models of wood flour (WF)/PVC composites before and after adding chitosan were studied using thermogravimetry (TGA) and nine common kinetic model functions (f(α)). The results indicated that the thermal degradation temperature of WF/PVC composites was delayed to a higher value after adding chitosan. The first-order reaction order (L1) model...

The thermal behavior of lignins from softwood and hardwood species has been investigated using thermogravimetry and differential scanning calorimetry. Klason Lignin from Pinus taeda and Klason lignin from Eucalyptus grandis were studied. The differential scanning calorimetry results showed that both Klason lignins studied presented similar glass transition temperature. Thermogravimetric results...

Galantamine hydrobromide was subjected to different stress conditions (acidic, alkaline, thermal, photolytic and oxidative). Degradation was found to occur under acidic, photolytic and oxidative conditions, while the drug was stable under alkaline and elevated temperature conditions. A stability-indicating reversed-phase liquid chromatographic method was developed for the determination of the d...

this research is aimed to undertake a comparative study on stability and thermal degradation kinetics of un-irradiated and high energy protons irradiated polyvinyl butyral (pvb) based on weight loss analysis and non-isothermal approaches. the weight loss by the un-irradiated pvb upon heating was found to be in two stages but due to high energy protons accelerated exposure following by chemical ...

The thermal degradation of polyethylene (PE) was carried out in the absence and presence ofcatalystes X-Zeolite and Silica-Alumina at different temperatures. The optimum PE/Catalysisratio was 0.25:0.05 g/g, which produced highest degradation value. PE and PE/Catalysis werecharacterized by thermogravimetric analysis. The thermal degradation properties of polymerhave been studied by Infrared spec...

The thermal degradation behavior of poly[(R)-3-hydroxybutyrate-co-16 mol%-4-hydroxybutyrate] (P(3HB-co-16 mol%-4HB)) was investigated based on spectroscopic analysis its pyrolyzates and two kinetic modeling approaches. Pyrolyzate revealed that trans-crotonic acid, cis-crotonic γ-butyrolactone, their oligomers (dimers trimers) were produced following P(3HB-co-16 mol%-4HB). analyses confirmed the...