Degradable recyclable

To increase the average molecular weight of somewhat degraded recycled polymer. ... 

Despite the enormous versatility and efficiency of CPO in organic synthesis, the natural functions of this enzyme are no less important. In addition to its role in the biosynthesis of caldariomycin and other metabolites (I). CPO is involved in the degradative recycling of humic and fulvic acids (315, 412, 2100, 2108, 2111-2113, 2234, 2235). Both Caldariomyces fumago and Curvularia inaequalis CPO, which... 

Fig. 10 Strain at break Vs. UV exposure time for polypropylene copolymer bars made from (a) virgin polymer (V) (b) virgin polymer + undegraded recyclate (U) (c) virgin polymer + photodegraded recyclate (P). Results for blends with recyclate contents of 10% and 25% are shown. (More details in Craig, I.H. White, J.R. Mechanical properties of photo-degraded recycled photo-degraded polyolefins. J. Mater. Sci. 2006, in press.)...

Figure 8.4. Intracellular sorting pathways of RME. The initial binding and uptake steps [including receptor clustering in eoated or noncoated pits, internalization of the receptor-ligand complex into coated vesicles (noneoated in the ease of potoc3d osis), and fusion of vesicles to form endosomes] are common to all pathways. After entry into acidic endosomes, ligand and receptors are sorted and trafficked independently, whieh may result in degradation, recycling or transcytosis of either molecule (seetext). L, ligand R, receptor lysosomes are depicted as shaded circles. (Adaptedfrom Ref 10.)...

Reuse of (cross-linked) polymers after degradative recycling,... 

Seyfang, A., Mecke, D. and Duszenko, M. (1990) Degradation, recycling, and shedding of Trypanosoma brucei variant surface glycoprotein. J. Protozool. 37 546-552. 

The rate at which the catalyst is lost or degrades has a major influence on the design. If degradation is rapid, the catalyst needs to be regenerated or replaced on a continuous basis. In addition to the cost implications, there are also environmental implications, since the lost or degraded catalyst represents waste. While it is often possible to recover useful materials from degraded catalyst and to recycle those materials in the manufacture of new catalyst, this still inevitably creates waste, since the recovery of material can never be complete. 

Catalyst is either degraded and requires changing or is lost from the reactor and cannot be recycled. 

Heterogeneous catalysts are more common. However, they degrade and need replacement. If contaminants in the feed material or recycle shorten catalyst life, then extra separation to remove these contaminants before the feed enters the reactor might be justified. If the cataylst is sensitive to extreme conditions, such as high temperature, then some measures can help to avoid local hot spots and extend catalyst life ... 

The recycling of engineering thermoplastics such as polyamides, ABS, and PTEE have been discussed (50). Property degradation as a result of use, recovery, and recycling is a concern. 

A significant part of HDPE is coUected from consumers for recycling uncoUected HDPE can be disposed of by landfiU or incineration. In landfiU, HDPE is completely inert, degrades very slowly, does not produce gas, and does not leach any poUutants into groundwater. When incinerated in... 

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