Surface modifying additives surfaces

Cardiovascular-functional polymers cover almost all categories of synthetic polymers and large numbers of biopolymers. They are used to build the device bulk, act as surface-modifying additives [SMA], and also formulate tissue adhesives [11-17]. 

P.H. BUt, K.G. Battiston, K.A. Woodhouse, J.P. Santerre, Surface immobilization of elastin-like polypeptides using fluorinated surface modifying additives, J. Biomed. Mater. Res. 96 (2011) 648-662. 

There are numerous possibilities for the synthesis of polyurethanes, which provides a distinct advantage for tuning the polymer properties to specific applications. Table 4 overviews some possibilities. In addition, the use of surface-modifying additives (typically 1% or less by weight) in polyurethanes can enhance their biostability, or add other functionality to the polymers. ... 

Surface-modifying additives Biostability, blood compatibility... 

Gu, Y. J., Boonstra, P. W., Rijnsburger, A. A., Haan, J., and van Oeveren, W., Cardiopulmonary bypass circuit treated with surface-modifying additives Clinical evaluation of blood bicompalibility, Ann ThoraeSurg., 1998 65(5) 1342-1347. 

Figure 3.12 (a) OCP transients and (b) potentiodynamic polarization plots recorded at a scan rate of 5 mV/s using Ru and Cu disc samples in alkaline (pH = 10) test solutions containing different surface modifying additives. The line plots in (b) represent experimental data, and the symbols placed on these lines are used to label the different systems used. 

Tan J, Brash JL. Nonfouling biomaterials based on polyethylene oxide-containing amphiphilic triblock copolymers as surface modifying additives synthesis and characterization of copolymers and surface properties of copolymer-polyurethane blends. J Appl Polym Sci 2008 108 1617-28. 

Blit PH, Battiston KG, Woodhouse KA, Santerre JP. Surface immobilization of elastin-Uke polypeptides using fluorinated surface modifying additives. J Biomed Mater Res Part A March 15, 2011 96A(4) 648-62. 

Surfaces are investigated with surface-sensitive teclmiques in order to elucidate fiindamental infonnation. The approach most often used is to employ a variety of techniques to investigate a particular materials system. As each teclmique provides only a limited amount of infonnation, results from many teclmiques must be correlated in order to obtain a comprehensive understanding of surface properties. In section A 1.7.5. methods for the experimental analysis of surfaces in vacuum are outlined. Note that the interactions of various kinds of particles with surfaces are a critical component of these teclmiques. In addition, one of the more mteresting aspects of surface science is to use the tools available, such as electron, ion or laser beams, or even the tip of a scaiming probe instrument, to modify a surface at the atomic scale. The physics of the interactions of particles with surfaces and the kinds of modifications that can be made to surfaces are an integral part of this section. 

Pulp-like olefin fibers are produced by a high pressure spurting process developed by Hercules Inc. and Solvay, Inc. Polypropylene or polyethylene is dissolved in volatile solvents at high temperature and pressure. After the solution is released, the solvent is volatilised, and the polymer expands into a highly fluffed, pulp-like product. Additives are included to modify the surface characteristics of the pulp. Uses include felted fabrics, substitution in whole or in part for wood pulp in papermaking, and replacement of asbestos in reinforcing appHcations (56). 

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... 

A good example of a surface-modified lens is the Sola/Bames-Hind Hydrocurve Flite lens, introduced in 1986. The material for the commercial Hydrocurve lens, bufilcon A [56030-52-5] contains methacrylic acid and has a high affinity for protein and subsequent deposition. The surface of the Flite lens was chemically modified with the addition of diazomethane (190) to reduce the surface charge. In vitro testing demonstrated a decrease in protein adsorption (191). 

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