Virgin reinforced polymer

Often the processes to gain recycled materials cause lower impacts than the production of virgin materials and, thus, the benefits from recycling are reflected in the assessment of closed loop recycling. If a material is down-cycled, e.g. thermoplastics or fibers in reinforced polymers, it could not be used again for the same application. A calculation of these recycling benefits leads to open loop recycling. 

Table 2.10 Comparison of flexural modulus of virgin reinforced and reinforced engineering polymers ...

Table 2.12 Comparison of Izod impact strength of virgin unreinforced and glass fibre reinforced polymers ...

The storage modulus of the reinforced polymer was improved appreciably over the storage modulus obtained for the virgin polymer over the temperature range -100°C to 150°C. 

Figure 1.5 a) Closed life cycle for CFRP. rCF Recycled-carbon fibre rCFRP recycled-carbon fibre reinforced polymer vCF virgin-carbon fibre and vCFRP virgin-carbon fibre reinforced polymer. Reprodnced with permission from S. Pimenta and S.X Pinho, Waste Management, 2011, 31, 378. 

Virgin carbon fibre reinforced polymer Virgin polyethylene terephthalate Wide-angle X-ray scattering Wood-plastic composite(s)... 

There are different types of plastics that are usually identified by their composition and/or performance. As an example, there are polymers that identify a material that is a pure material. They are NEAT polymers that identify materials with 2 7bthing Else Added To (Table 3.1). They are very rarely used. When additives, fillers, and/or reinforcement are included in the polymer it is called a plastic. A virgin plastic is one that has not been subjected to any fabricating process. It can be said that all plastics in order to be processed and meet product requirements contain additives, fillers, and/or reinforcements. 

Other tertiary recycling processes that have been developed include a Freeman Chemical Corp. process to convert PET bottles and film to aromatic polyols used for manufacture of urethane and isocyanurates. Glycolized PET, preferably from film, since it is often lower in cost than bottles, can be reacted with unsaturated dibasic acids or anhydrides to form unsaturated polyesters. These can then be used in applications such as glass-fiber-reinforced bath tubs, shower stalls, and boat huUs. United States companies that have been involved include Ashland Chemical, Alpha Corp., Ruco Polymer Corp., and Plexmar. Unsaturated polyesters have also been used in polymer concrete, where the very fast cure times facilitate repair of concrete structures. Basing polymer concrete materials, for repair or precast applications, on recycled PET reportedly leads to 5 to 10 percent cost savings and comparable properties to polymer concrete based on virgin materials. However, they are still approximately 10 times the cost of portland cement concrete. There appears to be little commercial application of these processes at present. 

Thus, alloys employing plastics compatibilized to PP, which could be derived from recycled interior scrap, would be attractive. Properties could be enhanced as needed by further blending with virgin polymer or through reinforcement with... 

The flexural moduli of a range of virgin and glass fibre reinforced engineering polymers are given in Table 2.9... 

Fibre-glass reinforced epoxy resins are used particularly in the power transmission, building products and pressure vessel markets. In the case of epoxy resins, tensile strengths fall from 600 in the virgin polymer to 68 MPa while the flexural modulus falls from 3 to 1.1 GPa. 

Licea-Claverie and co-workers [57] studied mechanical stress-strain, impact properties and also thermal properties of PA 6,6 (including some recycled PA) with mixed glass fibre and carbon fibre reinforcements and compared these properties with those of the virgin polymers. No dependence on mechanical properties because of increasing amounts of scrap in the composites was found up to 10.4 wt%. The recycled composites generally showed lower mechanical properties when compared with the virgin composites because of a poor matrix-fibre adhesion. 

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