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Plastics photodegradation

Methyl vinyl ketone is used as a comonomer in photodegradable plastics, and is an intermediate in the synthesis of steroids and vitamin A. It is highly toxic and faciUties handling over a threshold of 100 lbs (45.5 kg) are subject to special OSHA documentation regulations (273). [Pg.496]

This article highlights the growing problem of plastics waste disposal and then investigates modes of polymer degradation - thermal, chemical, mechanical, photodegradation, bio-degradation, solvolysis andglycerolysis. 4 refs. [Pg.76]

Degrade plastics (solid waste) by one of four processes biodegradation, photodegradation, chemical degradation, and hydrodegradation. [Pg.778]

This type of degradation can also be referred to as photodegradation or ultraviolet (UV) degradation. It includes photo-oxidation. It produces some of the more familiar signs of degradation of plastics embrittlement, discoloration and loss of transparency. [Pg.30]

Figure 8. Biodegradation of photodegraded LDPE. Cpm released (as C-CO2) demonstrates decomposition of the low molecular weight fraction of the plastic. Line A LDPE with accelerant of photodegradation Line B LDPE without accelerant. Maximum cpm released is less than 5% of total cpm added as LDPE. Data are from (45), Table 5. Figure 8. Biodegradation of photodegraded LDPE. Cpm released (as C-CO2) demonstrates decomposition of the low molecular weight fraction of the plastic. Line A LDPE with accelerant of photodegradation Line B LDPE without accelerant. Maximum cpm released is less than 5% of total cpm added as LDPE. Data are from (45), Table 5.
The processes of photochemistry are the same for polymers and small molecules. The Grotthus-Draper law sfafes fhat no photochemical reactions can occur unless a photon of lighf is absorbed. This means, for example, thaf many commercial plastics transparent in the near UV can undergo photodegradation only as a result of the absorption of light by impurities. [Pg.63]

F. Photodegradation of polymers-. Photodegradation of polymers assumes importance in two different contexts (i) ultraviolet and visible radiations are harmful to biopolymers like DNA, polysaccharides, proteins, etc. and an understanding of their mode of photolysis is important in life processes and (ii) more and more use of plastic materials in everyday life has created a problem of disposal. [Pg.227]

Biodegradable plastics, as well as those polymers that degrade in sunlight (photodegradable,... [Pg.240]

Photodegradable plastics Plastics designed to degrade under the influence of sunlight. [Pg.241]

See other pages where Plastics photodegradation is mentioned: [Pg.620]    [Pg.557]    [Pg.492]    [Pg.2089]    [Pg.686]    [Pg.68]    [Pg.257]    [Pg.620]    [Pg.620]    [Pg.557]    [Pg.492]    [Pg.2089]    [Pg.686]    [Pg.68]    [Pg.257]    [Pg.620]    [Pg.472]    [Pg.473]    [Pg.474]    [Pg.474]    [Pg.474]    [Pg.511]    [Pg.154]    [Pg.881]    [Pg.262]    [Pg.37]    [Pg.218]    [Pg.701]    [Pg.776]    [Pg.89]    [Pg.89]    [Pg.89]    [Pg.89]    [Pg.90]    [Pg.92]    [Pg.93]    [Pg.170]    [Pg.472]    [Pg.473]    [Pg.474]    [Pg.474]    [Pg.474]    [Pg.2]    [Pg.240]   
See also in sourсe #XX -- [ Pg.2 ]



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Photodegradable plastics

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