Surfaced-modified PET

Another category of PET-based copolymers with low molar levels of modifications are the materials produced by surface modification. The reader is directed to recent papers for discussions of surface-energy modification by such processes [77, 78], 

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Y Shin, K Son, D 1 Yoo, S Hudson, M McCord, S. Matthews and Y. J. Whang, Functional finishing of nonwoven fabric accessibility of surface modified PET iq)unbond by atmospheric pressure plasma treatment , Journal of Appl Polymer Sci, 20061004306-4310. 

Mixtures of PET/PVC (with virgin PET and surface modified PET, separately) were prepared by solution blending technique at different compositions and the values of (Ab) factor were obtained from comparision of experimental interaction coefficient for the mixture of components with the theoretical (b ) as computed from Williamson-Wright equation (10). 

PRT on glass and various surface-modified PET films. The films indicated with are those that have been immersed in distilled water for 7 days. (Reproduced from li, Y. L., et al.. Polymer, 45, 8779-8789, 2004. With permission from Elsevier.)... 

Physically or chemically modifying the surface of PET fiber is another route to diversified products. Hydrophilicity, moisture absorption, moisture transport, soil release, color depth, tactile aesthetics, and comfort all can be affected by surface modification. Examples iaclude coatiag the surface with multiple hydroxyl groups (40), creatiag surface pores and cavities by adding a gas or gas-forming additive to the polymer melt (41), roughening the surface... 

The thromboresistance of heparinized films, as shown in Table VI, was enhanced by higher hydrogel content since the concentration of hydroxylic groups on modified PET film surface, able to react with glutaralde-hyde in order to bind heparin, was higher. 

Affinity chromatography of streptavidin was performed on a PET chip. The microchannel was first filled with the dual-modified latex beads (as shown in Figure 6.3). The biotinylated beads were surface-modified with a temperature-sensitive polymer, poly(N-isopropylacrylamide (PNIPAAm, 11 kDa). When the temperature was raised above the lower critical solution temperature (LCST) of PNIPAAm, the beads aggregated and adhered to the channel wall, because of a hydrophilic-to-hydrophobic phase transition. Then streptavidin from a sample solution was captured by these adhered biotinylated beads. Thereafter, when the temperature was reduced below the LCST, the beads dissociated and eluted from the channel wall together with the captured streptavidin [203],... 

Alumina tri- hydrate ABS, A, E, N, P, PC, PET, PE, PP, PS, PVA, PVC, UF, UR. Alcan Alcoa AluChem. Climax Custom Grinders Franklin Industrial Georgia Marble R. J. Marshall Solem, Harwick H, FRF, SF UF series C-series, Hydral series AC-series Hydrax ATH series Polyfil series Custom grinds H-series Custom grinds of hydrate carbonate. KC-series A-100 series, A-200 series SB-series surface modified aluminas. Micral series. 

PET scrap suitable for glycolytic recycle includes production waste, fibers, film, flake, and bottles. In a practical system, major contaminants are separated from feedstocks, e.g., bottle waste is cleaned and separated from a polyethylene base, paper labels, metallic caps, and liners. For many end uses, colored PET must also be segregated. (Highly modified copolymers, glass-reinforced resin, fiber, or fabric blends are not suitable for glycolysis. These can only be recovered by methanolysis/hydrolysis.) Since reaction time depends on surface area, PET feedstocks must be reduced to relatively small particles by grinding, cutting, etc. 

Desai and Hubbell (34) have entrapped PEO chains to the surface by partially dissolving the base polymer in a suitable solvent Poly(ethylene terephthalate) (PET) with entrapped PEO (Mol. Wt 18,5(X)) decreased albumin adsorption by 80% and platelet adhesion by more than 95% as compared to the control PET. In addition, the adhesion of Staphylococcus epidermidis. Staphylococcus aureus, and Pseudomonas aeruginosa was r uced by 70-95% on PEO-modified PET compared to control PET... 

Figure 12. (a) Results ofpeel off tests for two-layer assembly made of unmodified membranes and membranes modified with PGMA layer, (b) AFM image (5x5 pm ) of surface of PET membrane covered with PGMA after the peel off test. Vertical scale 30 nm. 

Surface modified polyester fabric was padded through a two bowl vertical laboratory padder with two dips and two nips to give a wet pick up of 85 5% on the weight of the fabric with or without cross-liniking agent. After the padding, Neemazal treated PET fabric was dried at 85°C for 5 minutes and also at 130°C for 2 minutes. The fabric treated along with citric acid and BTCA was dried at 85°C for 5 minutes and simultaneously also cured at 1S0°C for 2 minutes. 

Jin SH, Park YB, Yoon KH. Rheological and mechanical properties of surface modified multi-waUed carbon nanombe-flUed PET composite. Compos Sci Technol December 2007 67 3434-41. 

Table 3. Atomic fractions of elements detected on the surfaces of reference and modified PET surfaces...

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