Showing papers on "Surface modification published in 1983"
TL;DR: In this article, the role of surface treatments for graphite fiber adhesion to epoxy matrix materials was investigated and it was shown that surface treatments designed to promote adhesion operate through a two-part mechanism: first, the treatments remove a weak outer fiber layer initially present on the fiber.
Abstract: Adhesion between graphite fibers and epoxy matrices is a necessary and sometimes controlling factor in achieving optimum performance. Manufacturers′ proprietary fiber surface treatments promote adhesion without providing a basic understanding of the fiber surface properties altered through their use. This study has combined fiber surface chemistry, morphology, interfacial strength measurements and fracture characterization in order to elucidate the role of surface treatments. The results of this investigation lead to the conclusion that surface treatments designed to promote adhesion to epoxy matrix materials operate through a two-part mechanism. First, the treatments remove a weak outer fiber layer initially present on the fiber. Second surface chemical groups are added which increase the interaction with the matrix. Increases in fiber surface area are not an important factor in promoting fiber-matrix adhesion. In some cases the upper limit to fiber-matrix interfacial shear strength is the intri...
524 citations
Book•
01 Jun 1983
281 citations
TL;DR: In this paper, the characteristics of the surface of various stainless steels are reviewed and the properties of these alloys that make them stainless is the formation of Cr2O3 on the surface.
Abstract: The characteristics of the surface of various stainless steels are reviewed. The property of these alloys that makes them stainless is the formation of Cr2O3 on the surface. It has been found that this protective layer can be modified relatively easily by heating, abrading, chemical treatment, or ion bombardment. Modification can be changes in the chemical composition of the surface layer or the formation of a layer of segregated material on the surface. These changes may alter the protective nature of the surface films. The outgassing characteristics of stainless steel surfaces also vary depending upon the treatment these surfaces receive.
98 citations
TL;DR: In this article, the authors describe detailed studies on the chlorination of vulcanized elastomer surfaces by an organic chlorine donor and the bonds obtained between such surfaces using a polyamide-cured epoxy adhesive.
Abstract: This paper describes detailed studies on the chlorination of vulcanized elastomer surfaces by an organic chlorine donor and the bonds obtained between such surfaces using a polyamide-cured epoxy adhesive. The bonds produced with a range of commercially important elastomers were found to retain their strength during extended seawater immersion better than those produced using the earlier surface treatments. The practical parameters of this technique have been investigated to establish the requirements for reliable and effective bonding. The chlorinated elastomer surfaces have been examined and explanations are offered for the changes observed.
68 citations
TL;DR: In this paper, an ESCA investigation has been made of the changes in surface functionalization for a series of polymers effected by means of low-powered inductively coupled rf plasmas excited in hydrogen and oxygen.
Abstract: An ESCA investigation has been made of the changes in surface functionalization for a series of polymers effected by means of low-powered inductively coupled rf plasmas excited in hydrogen and oxygen. Reactions in each case are confined to the outermost surfaces of the polymer films and the use of oxygen plasmas leads to extensive oxidative functionalization. Bisphenol-A polycarbonate and polyethylene terephthalate exhibit similar overall reactivities to both oxygen and hydrogen plasmas, while polystyrene is shown to be substantially more reactive than high-density polyethylene to the plasma treatments of interest in this work. Comparison has been made of the effects of straight hydrogen and oxygen plasmas and of sequential hydrogen/oxygen and oxygen/hydrogen plasma treatments.
51 citations
TL;DR: In an attempt to decrease friction between polymers commonly used as catheter materials, oxidation of polyethylene, fluorinated ethylene-propylene copolymer, poly(vinyl chloride), silicone rubber, and polystyrene surfaces was induced by exposing the polymers to radio frequency glow discharge (RFGD) in a helium environment.
Abstract: Double catheter systems consisting of a stiff outer catheter and a flexible, buoyant, flow-directed, inner catheter which is often balloon-tipped have been employed with increasing frequency recently in both therapeutic and diagnostic procedures. Their use, however, has been restricted because of the excessive friction generated between the two catheters. In an attempt to decrease friction between polymers commonly used as catheter materials, oxidation of polyethylene, fluorinated ethylene-propylene copolymer, poly(vinyl chloride), silicone rubber, and polystyrene surfaces was induced by exposing the polymers to radio frequency glow discharge (RFGD) in a helium environment. All polymers were surface characterized utilizing x-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and contact angle measurements before and after oxidation. This article describes the materials and methods used to fabricate and characterize the polymer surfaces and the results of the characterization. The results indicate that increases in oxygen concentration at the surface of the polymers and decreases in air-water contact angles occur with increased RFGD exposure time. Plateau values were usually obtained after 5-30 s exposure time, yet no apparent changes in surface topography were noted by scanning electron microscopy. The hydrophilic surfaces produced were stable for up to three months storage time in air.
41 citations
TL;DR: In this paper, structural changes in α-Al2O3 crystals implanted by 48Ti and 90Zr and subjected to thermal annealing have been investigated using ion scattering/channeling techniques.
33 citations
TL;DR: Results indicate that RFGD-treated SR generates less friction than untreated SR when dragged across all untreated and treated polymer surfaces, whether the medium is distilled water or an isotonic saline solution.
Abstract: The effects of the modification of polystyrene (PS), polyethylene (PE), poly(vinyl chloride) (PVC), silicone rubber (SR), and fluorinated ethylene propylene (FEP) copolymer by radio frequency glow discharge in a helium environment were presented in part I. The hydrated polymer surfaces were characterized by XPS, SEM, visual microscopy, and by contact angle measurements. In general, exposure of the polymers to RFGD produced an oxidized hydrophilic surface, yet the roughness of the surface was unaltered by the relatively mild plasma conditions used. In this article, the frictional behavior of oxidized and unoxidized SR, PE, and FEP in distilled water, isotonic saline, and blood plasma environments is examined experimentally. The results are discussed in relation to the properties generally believed to affect frictional phenomena and to the surface properties as determined in part I. Results indicate that RFGD-treated SR generates less friction than untreated SR when dragged across all untreated and treated polymer surfaces, whether the medium is distilled water or an isotonic saline solution. Friction is consistently lower in a blood plasma medium between all surfaces investigated, most probably because of the presence of adsorbed proteins at the polymer interfaces.
26 citations
TL;DR: In this paper, the surface properties of the clay mineral palygorskite and its derivatives in which the surface had been modified to various extents with the hexadecylpyridinium (HDP) cation were investigated.
26 citations
TL;DR: In this article, the authors present a method to distinguish unusual ionic species created in mass spectrometry from their congeners, isotopically selected, and supplied with well-defined translational energies.
Patent•
30 Sep 1983
TL;DR: In this paper, a low energy electron beam of an element to be imparted in polymeric material is formed and accelerated, the beam being subjected to electromagnetic separation so that only a high purity stream of the ion of this element impinges upon the substrate for implantation herein.
Abstract: A low energy electron beam of ions of an element to be imparted in polymeric material is formed and accelerated, the beam being subjected to electromagnetic separation so that only a high purity stream of the ion of this element impinges upon the substrate for implantation herein.
TL;DR: Substitution reactions of 2-bromomethyl-4-t-butoxycarbonyl-1,3-oxazole with several anions (C−, S−, O−, and I−) were performed to yield the desired products 7 a ∼ 7 k as discussed by the authors.
TL;DR: In this paper, the efficiency and durability of surface modification of poly(methyl methacrylate) [PMMA] by silicone containing graft and random copolymers were studied by contact angle measurement of water droplet.
Abstract: The efficiency and durability of surface modification of poly(methyl methacrylate) [PMMA] by silicone containing graft and random copolymers were studied by contact angle measurement of water droplet. The efficiency principally depended on the content of the siloxane; however, the durability of surface modification to hexane extraction differed according to the type of the silicone polymer and the siloxane content.
TL;DR: When trivalent rare-earth cations are added to crylolite flux, corundum crystals change from a complex platy form, without {112¯0} to a hexagonal form with only {112°0} and {0001} faces.
TL;DR: In this paper, the effect of surface modification of an n-type semiconductor on the electrochemical behavior of a soluble ferrocene derivative is reported and a mechanism involving diffusion of the electroactive substrate and/or an electron through the dye-loaded polymer film is suggested.
TL;DR: In this paper, it was shown that the value ΔυCD of CDCl3 in complexes cannot be used as a measure of basicity at least for sites with pKa ≥ 1.
Abstract: Chlroform destruction is shown to lead to surface modification which restricts the possibilities of its application to identify basic centers. The value ΔυCD of CDCl3 in complexes cannot be applied as a measure of basicity at least for sites with pKa≤+1.
Patent•
25 Oct 1983
TL;DR: A surface modifying composition for vulcanized rubber comprises a halogen-releasable halogenoid and a waxy substance having a melting point of not more than 100° C and is non-solvent type as mentioned in this paper.
Abstract: A surface modifying composition for vulcanized rubber comprises a halogen-releasable halogenoid and a waxy substance having a melting point of not more than 100° C. and is non-solvent type. In the surface modification of vulcanized rubber, the surface coated with the surface modifying composition is heated at 60°-150° C.
TL;DR: In this article, the authors describe recent results obtained with the implantation process and the mechanical and chemical properties of implanted iron or iron-based alloys, and describe how the implant can be used to improve surface layer properties such as wear and corrosion resistance.
01 Jan 1983
TL;DR: A variety of surface modification studies have recently been carried out in aluminum by several groups (Battaglin et al., 1981; Hussain et al. as mentioned in this paper, 1980; Peercy et al, 1982; and Picraux et al.'s 1980) with the objective of better clarifying the fundamental mechanisms involved for the case of metals.
Abstract: Ion implantation in combination with electron or laser beam pulsed heating provides a way to adjust the surface composition and microstructure of alloys independently of the usual equilibrium constraints. A variety of such surface modification studies have recently been carried out in aluminum by several groups (Battaglin et al., 1981; Hussain et al., 1980; Peercy et al., 1982; and Picraux et al., 1980. Selected results from these studies are summarized in the present chapter, with the objective of better clarifying the fundamental mechanisms involved for the case of metals. Thus for a single host system, we illustrate the various aspects of directed energy modification of materials discussed individually in previous chapters.
TL;DR: In addition to the accumulation of the implanted species, a considerable number of processes can affect the composition of an alloy in the surface region during ion bombardment as mentioned in this paper, such as collisions of energetic ions with atoms of the alloy induce local rearrangement of atoms by displacements, replacement sequences and spontaneous migration and recombination of defects within cascades.
Abstract: In addition to the accumulation of the implanted species, a considerable number of processes can affect the composition of an alloy in the surface region during ion bombardment. Collisions of energetic ions with atoms of the alloy induce local rearrangement of atoms by displacements, replacement sequences and by spontaneous migration and recombination of defects within cascades. Point defects form clusters, voids, dislocation loops and networks. Preferential sputtering of elements changes the composition of the surface. At temperatures sufficient for thermal migration of point defects, radiation-enhanced diffusion promotes alloy component redistribution within and beyond the damage layer. Fluxes of interstitials and vacancies toward the surface and into the interior of the target induce fluxes of alloying elements leading to depth-dependent compositional changes. Moreover, Gibbsian surface segregation may affect the preferential loss of alloy components by sputtering when the kinetics of equilibration of the surface composition becomes competitive with the sputtering rate. Temperature, time, current density and ion energy can be used to influence the individual processes contributing to compositional changes and, thus, produce a rich variety of composition profiles near surfaces. 42 references.
Patent•
21 Feb 1983
TL;DR: In this article, the surface of a polymeric material (e.g., polyethylene, nylon 6, etc.) is treated with corona discharge in open atmosphere to impose energy of 0.1m-Joule 2 W100 Joule/cm 2 preferably for 0.01W10min, and is made to contact with one or more radically polymerizable monomers in the form of vapor or solution.
Abstract: PURPOSE: To modify the surface of a polymeric material so as to enable the control of the degree of grafting, without causing damage to substrate, by treating the surface of the polymeric material with corona discharge in open atmosphere, and carrying out the graft polymerization of a radically polymerizable monomer to the surface. CONSTITUTION: The surface of a polymeric material (e.g. polyethylene, nylon 6, etc.) is treated with corona discharge in open atmosphere to impose energy of 0.1m-Joule/cm 2 W100 Joule/cm 2 preferably for 0.01W10min, and is made to contact with one or more radically polymerizable monomers (e.g. styrene, acrylamide, etc.) in the form of vapor or solution. The monomers are grafted to the surface of the polymeric material e.g. by thermal polymerization, redox reaction, etc. to achieve the objective modification of the surface of the polymeric material. COPYRIGHT: (C)1984,JPO&Japio
Patent•
12 Oct 1983
TL;DR: In this article, the surface modification of a fine granular magnetic iron oxide with the particle size of about 1-0.7mum comprising needle gamma-iron oxide obtained from alphaFe2O3.
Abstract: PURPOSE:To improve the dispersibility of ferromagnetic powder into binder and adhesiveness thereof with said binder, by modifying the surface of the ferromagnetic powder with a coupling agent. CONSTITUTION:Fine granular magnetic iron oxide with the particle size of about 1-0.7mum comprising needle gamma-iron oxide obtained from alphaFe2O3.H2O as a starting stock material is subjected to surface modification by a coupling agent which is a liquid substance with M.W. of 10,000 or less such as isopropyl triisostearoyl titanate. The coupling agent forms a monomolecular membrane or a di-molecular membrane and does not lower magnetism while can be bonded with a magnetic material and is chemically reacted with moisture to remove the same as well as prevents void formation. Because the bondability of the magnetic material and a binder is improved, a magnetic coating with high density and excellent anti-wear property can be obtained.
Patent•
07 Mar 1983
TL;DR: In this paper, a mixture of a colloid of an inorganic compound forming hydrophilic gel and a hydrophobic colloid (preferably colloidal graphite) is applied to the surface of a synthetic fiber weldable in heat-elongation and/or heat-treatment process, and the mixture is dried to obtain the surface modified fiber.
Abstract: PURPOSE: To prevent the mutual welding of the filaments of synthetic fiber exhibiting weldability in the heat elongation and heat-treatment process, by applying a mixture of a hydrophobic colloid and a colloid of inorganic compound forming hydrophilic gel to the surface of the fiber, and drying the applied colloid mixture. CONSTITUTION: A mixture of a colloid of an inorganic compound forming hydrophilic gel (preferably a silicate compound, especially hydrated aluminum silicate or magnesium fluorosilicate) and a hydrophobic colloid (preferably colloidal graphite) is applied to the surface of a synthetic fiber weldable in heat-elongation and/or heat-treatment process (preferably an aromatic copolyamide) by dipping, and the mixture is dried to obtain the surface-modified fiber. The mutual welding of filaments can be prevented effectively even if the fiber is composed of a large number of filaments. COPYRIGHT: (C)1984,JPO&Japio
01 Jan 1983
TL;DR: The use of surface active agents as integral surface treatments has been investigated by Zisman and coworkers as discussed by the authors, who have pointed to the suitability of fluorinated surfactants and polysiloxane block copolymers.
Abstract: Surface properties of polymers are known to be of considerable importance in applications such as coatings, adhesives, films, fibers and moldings. Hydrophilic modification of nonpolar polymers is useful to improve adhesion, wetting, coating and antistatic properties. Hydrophobic modification of polar polymers is useful to improve water and oil repellency, and frictional properties. Among many surface modification techniques including chemical, UV and plasma treatments, surface accumulation of functional segments by using tailored graft copolymers appears to be most promising to obtain a controlled surface structure for any particular application. The use of surface active agents as integral surface treatments has been investigated by Zisman and coworkers1,2, who have pointed to the suitability of fluorinated surfactants and polysiloxane surfactants. Ten years ago, Gaines3 and Owen4 have independently shown that dimethylsiloxane block copolymers do concentrate at the surface when they are added, in low concentrations, during fabrication of solid polymers. These blockcopolymers appear to be particularly suitable additives for practical application because they are effective at very low levels, resist removal from the surface by rinsing and are useful for permanent surface modification.
Patent•
28 Nov 1983
TL;DR: In this article, a polymethacrylate ester molding is plasma-treated to form a modified layer on its surface, and the modified layer is washed with a solvent which does not substantially dissolve the base material of the molding, such as acetone.
Abstract: PURPOSE:To obtain a film extremely excellent in adhesion to a plastic molding, by plasma-treating the molding to form a modified layer on its surface, washing the modified layer with a solvent and then depositing an inorganic hard substance on the surface. CONSTITUTION:A plastic molding having excellent transparency, such as a polymethacrylate ester molding, is plasma-treated to form a modified layer on its surface. The modified layer is washed with a solvent which does not substantially dissolve the base material of the plastic molding, such as acetone. The solvent remaining on the surface is removed by, for example, drying, and the surface modification of the molding is carried out by depositing a film of an inorganic hard substance on the surface of the molding, for example, by vacuum deposition.
Patent•
07 Mar 1983
TL;DR: In this paper, a hologen-containing plasma chemical reaction is conducted, as the electron temperature is controlled in a specific range near the surface of the substrate to effect uniform deposition and surface modification with high thickness.
Abstract: PURPOSE:A hologen-containing plasma chemical reaction is conducted, as the electron temperature is controlled in a specific range near the surface of the substrate to effect uniform deposition and surface modification with high thickness. CONSTITUTION:From the inlet A of the plasma reaction chamber T, a gas containing a halogen compound, in case of deposition, or containing halogen molecules in case of surface modification is introduced and the electron temperature near the substrate surface 7 is controlled by adjusting the position of the subsbrate or the coil shape so that it ranges from 10,000 to 40,000 deg.K as measured with a probe 1 to effect the surface treatment.
Patent•
30 Jun 1983
TL;DR: In this article, a deuterium lamp is used for surface treatment of a solid substance such as the fabrication of a membrane, etching, purification, or surface modification.
Abstract: PURPOSE:To prevent adverse influence to the human body by enhancing reaction efficiency, by performing the surface treatment of an object to be treated by activating predetermined gas while appropriately selecting the wavelength of light from a deuterium lamp. CONSTITUTION:A wavelength or wavelength band selecting means 3 such as a filter is provided to the light path 30 of the light from a deuterium lamp 1 equipped with a water cooling means 2 and having a continuous light emitting region of 160-400nm and the interior of a reaction chamber 6 is irradiated with light through an optical window 5. The reaction chamber 6 can be held under an air-tight state and a gas introducing system 9 and a gas exhaust system 10 are connected to said chamber 6 while an object 8 to be treated on a support table 7. By this mechanism, ultraviolet rays with an arbitrary wavelength and/or arbitrary wavelength band of 160-400nm can be utilized and predetermined gas is activated to make it possible to perform the surface treatment of a solid substance such as the fabrication of a membrane, etching, purification or surface modification.