Showing papers on "Self-healing hydrogels published in 1983"
TL;DR: A bioerodible hydrogel based on water-soluble unsaturated polyesters crosslinked through the double bonds and capable of immobilizing water- soluble macromolecules has been developed.
123 citations
TL;DR: In this article, the formation of gel during the -irradiation of aqueous solutions of acrylamide is reported and the influence of the dose and dose rate on the yield of this process was investigated for acarlamide concentrations ranged from 0, 28 to 6, 0 mol dm -3.
54 citations
TL;DR: In this paper, the interaction of radiation-grafted hydrogels with blood and its components, both in vitro and in vivo, has been studied, and it has been found that as the hydrogel water content increases, it tends to adsorb fewer protein molecules, and to desorb them more readily in vitro, but to adhere the thrombi less readily in the in vivo canine ring tests.
43 citations
Patent•
29 Aug 1983
TL;DR: In this article, copolymers having improved machining and water resistant properties are produced using a monomer containing an adduct protecting group, particularly an alkyl boronic acid adduct, of glyceryl acrylate or glycery-l methacrylate, in combination with an alkinyl acrylated or methaclated, and optionally a glycidyl acricrylated and/or methacylated, and they are removed to provide a hydrogel useful as a contact lens material.
Abstract: Copolymers having improved machining and water resistant properties are produced using a monomer containing an adduct protecting group, particularly an alkyl boronic acid adduct, of glyceryl acrylate or glyceryl methacrylate, in combination with an alkyl acrylate or methacrylate, and optionally a glycidyl acrylate or methacrylate. After machining and shaping, the adduct is removed to provide a hydrogel useful as a contact lens material.
26 citations
TL;DR: The use of protein hydroxy ethylmethacrylate (HEMA) hydrogels to control cell morphology and growth, as well as the synthesis of extracellular matrix components, is described in this communication.
26 citations
TL;DR: In this paper, the surface of poly(ether urethhane) is modified by preparing gradient interpenetrating polymer networks (IPNs) with polyyacrylamide hydrogels.
Abstract: The surface of poly(ether urethhane) is modified by preparing gradient interpenetrating polymer networks (IPNs) with polyyacrylamide hydrogels. Soveral experimental methods are used for preparing the gradient IPNs. Attenuated total reflection Fourier transform infrared (ATR-FTIR) is used as the main characterization technique.
23 citations
TL;DR: In this paper, a very hydrophilic vinyl lactam, a hydrophobic alkyl acrylate, and a hexafunctional methacrylate copolymerizaton in vacuo at 21/sup 0/C initiated by gamma-gamma-irradiation from a /sup 60/Co source is employed.
Abstract: A considerable literature covers the preparation and properties of hydrogels for biomedical applications. The failure to emphasize practical problems in these reports should not be taken to imply, however, that such difficulties are absent. The preparative techniques usually involve polymerization or copolymerization in the presence of a crosslinking agent. Bulk polymerization is often used, or, alternatively, reaction in an aqueous medium if the monomers are fairly soluble in water. The present authors are currently studying copolymers made from a very hydrophilic vinyl lactam, a hydrophobic alkyl acrylate, and a hexafunctional methacrylate. The desired properties of the hydrophilic product include (a) optical and textural homogeneity, (b) minimal content of residual monomers and (c) ease of machinability. Bulk copolymerizaton in vacuo at 21/sup 0/C initiated by ..gamma..-irradiation from a /sup 60/Co source is employed. Resolution of certain experimental problems, which arose in this work, should be of interest to others in the field, and this constitutes the theme of the present communication.
17 citations
TL;DR: The crosslinking density and pore sizes of poly(2-hydroxyethyl methacrylate) (polyHEMA) hydrogels have been measured and correlated with the diffusion characteristics of a solute through the polymer as mentioned in this paper.
Abstract: The crosslinking density and pore sizes of poly(2-hydroxyethyl methacrylate) (polyHEMA) hydrogels have been measured and correlated with the diffusion characteristics of a solute through the polymer. Studies indicated that diffusion is hindered both by obstruction by the polymer chains and by the immobility of the solvent within the gel. Values for the diffusion coefficient of a solute, D, and interaction parameters between the solvent and polymer suggest that as the concentration of crosslinking agent in the polymer network increases, the hydrophohicity of the polymer and the mobility of the solvent in the gel increase. Increased crosslinking however, increases the effectiveness of the obstruction effect, and the overall effect is a reduction in D.
14 citations
TL;DR: These findings suggest that the cells cultured on collagen hydrogels are ultrastructurally indistinguishable from those cultured on tissue-culture plastic.
8 citations
Patent•
30 May 1983
TL;DR: In this paper, non-tacky or low-tack particles of hydrogel polymers are produced by extruding a polymer gel through perforated disks and cutting the gel strands in a manner known per se, the release agent being fed to the extruder together with the polymer gel.
Abstract: Non-tacky or low-tack particles of hydrogel polymers are produced by extruding a polymer gel through perforated disks and cutting the gel strands in a manner known per se, the release agent being fed to the extruder together with the polymer gel, a release agent which is sparingly or not soluble in water, preferably in the working area of the extruder screw .
TL;DR: The polyelectrolyte hydrogels do not deplete Antithrombin III from blood and there is no activation of factor XII according to an in vitro kallikrein generation test, but in a very sensitive test for factor XII activation a slight activation of this factor was observed.
01 Jan 1983
TL;DR: The principal properties and available information on hydrogels prepared by synthetic methods are reviewed in this article, where the authors do not discuss the properties and properties of hydrogel made from natural polymers.
Abstract: The principal properties and available information on hydrogels prepared by synthetic methods are reviewed. Hydrogels made from natural polymers are not discussed.
01 Jan 1983
TL;DR: In this paper, the swelling properties of polyhydroxyalkyl acrylates in water were investigated and the degree of crosslinking, concentration of additives in the water and the amount of water used in the polymerization process.
Abstract: Hydrogels, in the swollen state, exhibit poor mechanical properties which need to be improved to increase their utility. Polymeric materials with a wide range of physical properties suitable for a broad variety of applications can be prepared using hydrophobic monomers with a variety of crosslinkers. The polymerization of 2-hydroxyethyl methacrylate(HEMA) with ethylene glycol dimethacrylate(EGDMA) in the presence of organic peroxides gave a hydrophilic copolymer useful for coatings, mouldings and carriers for biologically active substances (1). The swelling properties of polyhydroxyalkyl acrylates in water depends to a certain extent on the degree of crosslinking, concentration of additives in the water and the amount of water used in the polymerization process. When HEMA was polymerized in aqueous solution with high water content polymer precipitates out from the monomer and yields opaque gels or porous sponges (2). Mechanical behavior of poly(HEMA) hydrogels prepared in the presence of various concentrations of crosslinking agents and diluents has been investigated. A copolymer prepared from a hydroxyalkyl (meth)acrylate, a crosslinking agent such as EGDMA and an unsaturated acid like methacrylic acid are suitable for manufacturing contact lenses (3).