Accelerated and natural ageing of PVC foils

Abstract

The photooxidation stability of PVC foils with various thicknesses (0,4; 0,2; 0,3 and 0,14 m m ) intended f o r agricultural use is investigated during accelerated and natural ageing. The surface state variations are investigated by surface crazing, total c o l o u r variation and chemical composition of t h e surface layer (IR-spectra of MIR-IR-spectroscopy). The foil volume variations are investigated by m e a n s of differential IR-spectra, light transmission decrease and t h e specific elongation. An analogy in t h e PVC f o i l s properties o f 0,4 mm thickness both f o r accelerated and natural ageing is observed. It is established t h a t during t h e 12 months induction period of t i m e f o i l s change negligibly t h e i r properties. The original properties of foils with thickness of 0,14 mm weathering f o r 15 months have changed less. For a period of 12 months t h e changes P a p e r presented a t the lath Colloquium o f Danubian Countries, f o r "Natural and artificial ageing of plastics" in Villach (Austria) J u n e 24 -26, 1987. 0 1988 Hilthig & Wcpf Vcrlag, B u d 0003-3146/88/%03.00

Prediction of service lifetime and performance of a prosthetic thermoplastic

“…Correlations between the natural degradation of polymer properties and results obtained in the laboratory have been r e p~r t e d .~-~ Although many variables are involved in influencing the correlations, '-14 it appears that a comparative (not absolute) relationship can still be established. '"16 Many material properties which are degraded by weathering have been examined chemical composition, color, 'a8 hardness, 16,17 tensile properties, [5][6][7][8] and impact resistance? An exponential equation appears to adequately describe the most common type of relationship between artificial and natural weathering.6-8 However, since many variables are involved during weathering, the correlations reported in other studies should be restrictively applied to specific polymers.…”