Degraded plastics effects

The effects of UV radiation on degradable plastics are usually confined to the exposed surface layers. Tlie general effect is one of embrittlement. Tensile strength may either increase or decrease, but the elongation upon breaking is always reduced. A loss of impact... 

Guo and coworkers (29) examined the chemical stability of lyophilized quinapril HC1 as a function of initial solution pH. Lyophilization of different quinapril solutions produces mixtures of amorphous quinapril and its neutralized form, with glass transition values between the Tg values of quinapril and neutralized quinapril. As the fraction of quinapril increases the rate of chemical degradation increases relative to that of quinapril HC1 alone. This is most likely caused by the plasticizing effects of neutralized quinapril. 

This paper describes the effects of UV light, the most significant aspect of outdoor weathering, on a variety of Degradable Plastics and also discusses the extent of biodegradability of the photodegraded samples. 

The increase in drug degradation rate in solid polymer matrices with increasing water content can also be attributed to the plasticizing effect of water. As shown in Fig. 1 1 1, 465 the... 

Meaningful research should be carried out into the effects of degradable plastics in the environment. 

Nakatsuka, S. and Andiady, A. (1994) Studies on enhanced degradable plastics. III. The effect of weathering of polyethylene and (ethylene-carbon monoxide) copolymers on moisture and carbon dioxide permeability. Journal... 

In both plasticized (semi-rigid and flexible) PVC materials as well as PVC in solutions, the rate of their thermal degradation and effective stabilization are caused by essentially different fundamental phenomena in comparison to aging of PVC in absence of the solvent. 

---