Polyurethane grafting

In the case studies to follow, both hydrophilic and hydrophobic polyurethanes are used to affect remediation of polluted air and water. We will not discuss conventional wastewater systems because they represent large public works projects that dot the developed world. The first three case studies cover the use of reticulated foam as a scaffold for the remediation of polluted air. Another involves the use of a hydrophilic foam as a scaffold for a biofilter to treat aquaculture wastewater, permitting its return to the system (closing the recycle loop). Lastly, we will review our work on a composite of hydrophilic polyurethane grafted onto a reticulated foam to treat VOC-contaminated air. 

FIGURE 5.11 Comparison of elimination capacities of reticulated foam and hydrophilic polyurethane-grafted reticulate. 

FIGURE 6.5 CeU adhesion on a hydrophilic polyurethane-grafted reticulated foam imbibed with fibronectin. 

It should be pointed out that this method relies on the efficient dispersion of nanotubes in the relevant solvent. The choice of solvent is generally made based on the solubility of the polymer. However, pristine nanotubes usually cannot be well dispersed in most solvents. To get around this problem, Xia et al. (17) compared the dispersion of MWNT-graft-PU, MWNT-OH and raw MWNTs in 0.2% aqueous solution of sodium lauryl sulfate. The results showed that MWNT-graft-PU has a better dispersion stability compared to MWNTs and MWNT-OH. The incorporation of polyurethane-grafted carbon nanotubes had a better reinforcing effect compared to the raw carbon nanotubes. This should be attributed to the improved interfacial interaction between polyurethane matrix and carbon nanotubes. 

K. Fujimoto, H. Inoue, Y. Ikada, Protein adsorption and platelet adhesion onto polyurethane grafted with methoxy-poly(ethylene glycol) methacrylate by plasma technique, J. Biomed. Mater. Res. 27 (12) (1993) 1559-1567. 

M. Stoiber, D. Bernhard, H. Schinia, Healing characteristics of elec-trospun polyurethane grafts with various porosities, Acta Biomater. 9 (4) (2013) 6032-6040. 

In some cases, grafting is used to form the copolymers. Examples of chains combined with PDMS in this way include polyfethylene oxide) fluorinated chains, alkyl acrylates and alkyl methacrylates, polyfvinyl alcohol), polyfether sulfones), and polyurethanes. Grafting has also been used to introduce t-butylamine and t-butylammonium biocidal functionalities, and to improve the adhesion of silicone rubber to polyurethane. In other cases, the siloxane groups are simply placed on the ends of chains, such as onto some polybenzoxazines. ... 

A. Damusis and K. C. Frisch, Flexibilized Polyester Resin Compositions Containing Polyurethanes Modified with Vinyl Monomers and Process Therefore, U.S. Pat. 3,448,172 (1969). Polyester/polyurethane grafted semi-SINs. 

Ikada Y. Water lubrication of polyurethane grafted with dime-thylacrylamide for medical use. Wear 1993 161(1/2) 179-185. 24. 

Korematsu A, Takemoto Y, Nakaya T, Inoue H. Synthesis, characterization and platelet adhesion of segmented polyurethanes grafted phospholipid analogous vinyl monomer on surface. Biomaterials 2002 23 263-71. 

Pinchuk L, Martin Jr JB, Esquivel MC, MacGregor DC. The use of silicone/polyurethane graft polymers as a means of eliminating surface cracking of polyurethane prostheses. J Biomater Appl October 1988 3(2) 260-96. 

Xia H, Song M. Preparation and characterisation of polyurethane grafted single-walled carbon nanombes and derived polyurethane nanocomposites. J Mater Chem March 2006 16 1843-51. 

Chen KY, Kuo JF. Surface characterization and platelet adhesion studies of aliphatic polyurethanes grafted by fluorocarbon oligomers effect of fluorocarbon chain length and carboxylic acid group. J Mater Sci Mater Med 2002 13(1) 37—45. 

Bergmeister H, Schreiber C, Grasl C, Walter I, Plasenzotti R, Stoiber M, et al. Heahng characteristics of electrospun polyurethane grafts with various porosities. Acta Biomater 2013 9 6032--40. 

Xia H and Song M (2006) Preparation and characterization of polyurethane grafted single-walled carbon nanotubes and derived polyurethane nano composites, J Mater Chem 16 1843-1851. 

Masuda, S. et al, Vascular endothelial growth factor enhances vascularization in microporous small caliber polyurethane grafts. Asaio J, 1997.43(5) M530-34. 

Polyurethane grafts with acrylic acid Plasma modification of surface 31... 

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