Search results for "accelerated ageing"
showing 3 items of 3 documents
Durability of basalt/hemp hybrid composites
2017
This study focused on the performance of injection-molded short hemp fibre and hemp/basalt fibre hybrid high density polyethylene composites. Results showed that hybridization with basalt fibre enhanced the performance properties. Analysis of fiber length distribution in the composite and fracture surface was performed to study the fiber breakage and fracture mechanism. Prolonged moisture absorption and accelerated ageing of short hemp fibre and hemp-basalt hybrid reinforced thermoplastic composites was addressed. Ageing in water did not result in a reduction of the strength of the composite samples, while it was found to decrease stiffness of hemp fibre reinforced composites. Mechanical pr…
Effect of accelerated ageing on the mechanical behaviour of basalt/hemp hybrid composites
2017
The remarkable concerns related to environmental pollution have triggered a lot of studies aimed at decreasing the environmental impact of polymer composites. A possible way to achieve this goal is the replacement of glass fibres with natural ones. In particular, lignocellulosic fibres are of considerable interest because they are renewable resources and are characterized by low cost, low density, thermal and acoustic insulation, biodegradability and recyclability. Despite these favourable attributes, cellulosic fibre reinforced composites do not provide mechanical properties comparable with those of glass fibre composites and, most importantly, their susceptibility to moisture absorption c…
Influence of accelerated ageing conditions on the process of polyolefines degradation
2003
The process of polymers weathering and the methods of polymers weathering and accelerated ageing investigations were characterized. Accelerated ageing tests of polyethylene and polypropylene samples have been done in laboratory conditions. The ageing time (up to 400 h) influence, at various levels of ageing factors: UV radiation intensity (80—190 W/m2), temperature (35—55 °C) and humidity (30—90%), on the changes of the structures of polymers investigated (shares of carbonyl and olefinic groups from FT-IR spectra — Fig. 1, 2, 4 and 5), on the changes of polymers molecular weights (Fig. 3 and 6, Table 1) and on the changes of mechanical properties during tension (Table 1) has been investigat…