Showing papers on "Surface modification published in 1970"

Surface modification of carbon fibers

Abstract: A PROCESS IS PROVIDED FOR MODIFYING THE SURFACE CHARACTERISTICS OF A CARBONACEOUS FIBROUS MATERIAL (I.E. EITHER AMORPHOUS CARBON OR GRAPHITIC CARBON) AND TO THEREBY FACILITATE ENHANCED ADHESION BETWEEN THE FIBROUS MATERIAL AND A MATRIX MATERIAL. THE CARBONACEOUS FIBROUS MATERIAL IS CONTACTED FOR RELATIVELY BRIEF RESIDENCE TIME WITH AN EXCITED GAS SPECIES AT A MODERATE TEMPERATURE OF ABOUT 20 TO 325*C. GENERATED BY APPLYING HIGH FREQUENCY ELECTRICAL ENERGY IN PULSED FROM TO A GASEOUS MIXTURE COMPRISING ING AN INERT GAS AND A SURFACE MODIFICATION GAS. COMPOSITE ARTICLES OF ENHANCED INTERLAMINAR SHEAR STRENGTH MAY BE FORMED BY INCORPORATING THE FIBERS MODIFIED IN ACCORDANCE WITH THE PRESENT PROCESS IN A RESINOUS MATRIX MATERIAL.

Surface modification of carbon fibers

Abstract: A process is provided for modifying the surface characteristics of a carbonaceous fibrous material (either amorphous carbon or graphitic carbon) and to thereby facilitate enhanced adhesion between the fibrous material and a resinous matrix material. The fibrous material is initially heat treated in an inert gaseous atmosphere, and is subsequently heated in a gaseous atmosphere which includes a substantial quantity of ozone under conditions found capable of producing the desired surface modification. Composite articles of enhanced interlaminar shear strength are formed by incorporating the fibers modified in accordance with the present process in a resinous matrix material.

Enhancement of the surface characteristics of carbon fibers

Abstract: An improved process is provided for modifying the suface characteristics of a carbonaceous fibrous material (either amorphous carbon or graphitic carbon) and to thereby facilitate enhanced adhesion between the fibrous material and a matrix material. The fibrous material is continuously passed at a relatively rapid rate through a heating zone containing a minor quantity of gaseous molecular oxygen under conditions found suitable for bringing about the desired surface modification. Composite articles of enhanced interlaminar shear strength may be formed by incorporating the fibers modified in accordance with the present process in a resinous matrix material.

Influence of solar radiation reflectance on water evaporation

Abstract: The evaporation of a water reservoir may be reduced by increasing the reflectance of solar energy by the water surface. Such a change in reflectance will require a surface modification such as the application of a special surface film or monolayer with good reflecting properties. Since colored materials reflect at wavelengths at which the solar energy has its peak intensity, colored monolayers and artificially dyed monolayers were studied experimentally. A large number of dyes were investigated, but in no instance did the dyes color the monolayer or form a monolayer themselves. A yellow silicone oil film on a water surface was found experimentally to reflect solar energy about 1.7 times better than a plain water surface and also to reduce the evaporation rate. In addition, the film was extremely difficult to remove from a water surface. Its durability is a real advantage where there is the need to constantly resupply monolayers as in present evaporation suppression techniques. Analytical studies were conducted to determine the evaporation reduction resulting from increased solar reflectance. The transient energy equation for an element of a water surface was solved by numerical methods. The analytical model gave an average evaporation suppression by cetyl alcohol of 22.6%, which is consistent with previous experimental work. Results for monolayers with hypothetical reflectance properties and with the diffusion properties of a cetyl alcohol monolayer showed average evaporation reductions of 25 to 45%, depending on the reflection properties.

Surface modification of carbon fibers

Abstract: A CONTINUOUS PROCESS IS PROVIDED FOR MODIFYING THE SURFACE CHARACTERISTICS OF A CARBONACEOUS FIBROUS MATERIAL (EITHER AMORPHOUS CARBON OR GRAPHIC CARBON) AND TO THEREBY FACILICATE ENHANCED ADHESION BETWEEN THE FIBROUS MATERIAL AND A MATRIX MATERIAL. THE FIBROUS MATERIAL IS CONTINUOUSLY PASSED THROUGH A HEATING ZONE CONTAING GASEOUS CARBON DIOXIDE UNDER CONDITIONS FOUND SUITABLE FOR BRINGING ABOUT THE DESIRED SURFACE MODIFICATION. COMPOSITE ARTICLES OF ENHANCED INTERLAMINAR SHEAR STRENGTH MAY BE FORMED BY INCORPORATING THE FIBERS MODIFIED IN ACCORDANCE WITH THE PRESENT PROCESS IN A RESINOUS MATRIX MATERIAL.

A Survey Of Surface Treatments To Improve The FrettingFatigue Resistance Of Ti-6Al-4V

Abstract: The effects of surface modification treatments such as shot peening, ion implantation (carbon and nitrogen), surface lubrication (soft coating), laser gas nitriding and various combinations thereof, on the fretting fatigue resistance of Ti-6Al-4V have been investigated. The best of these surface treatments appears to be shot peening. While ion implantation improves the base metal fretting fatigue resistance to some extent, the fretting fatigue life of shot peened Ti-6Al-4V is reduced by the ion implantation treatment or the application of a soft coating. The fretting fatigue life of laser nitrided Ti-6Al4V is inferior to that of the base metal and this occurs as a result of the inferior surface finish and brittle nature of the nitrided surface.

Hydrophilic and antistatic treatment for polymers

Abstract: A surface modification to impart antistatic and hydrophilic properties to polyurethanes or polyamides by reaction with acrylonitrile and a base.

Electrophoresis and Adsorption Studies of Proteins and Their Derivatives on Colloids and Cells

Abstract: The work to be described concerns the adsorption of some proteins and their derivatives at the solid/water interface. This study is derived from previous work on the modification of model particles by adsorption in an attempt to investigate the problem of what constitutes “foreignness” as far as the body is concerned. Specifically, a cell system in mammals, the reticulo-endothelial system identifies foreign particles from native ones and removes them by phagocytosis. The mechanism of this process is but poorly understood and previous work has been directed toward the initial step of recognition. This was studied using a model colloidal system of polystyrene latex (PSL) with its surface properties modified by adsorption of various macromolecules (1). It was found that such surface modification influenced the organ distribution of injected particles.