Abstract: Improved compositions for scavenging oxygen are disclosed. These materials, characterized by low degree crystallinity and a glass transition temperature of <-10.degree. C., have high oxygen scavenging rates at low temperatures. The composition comprises an ethylenically unsaturated hydrocarbon and a transition metal catalyst and can be incorporated into various types of layers. It is preferable that the composition be incorporated into layers of multilayered articles used for packaging oxygen-sensitive products such as food products.
Abstract: Flexographic photosensitive printing plates are made with formulations comprising block polymers having an architecture of BA, CBA or CBCA, where A is poly(vinylpyridine), B is poly(butadiene) or poly(isoprene) and C is styrene. The polymers may be quaternized or neutralized with an organic acid. When made with quaternized polymers, the plates after imaging with UV may be developed in aqueous solutions. The block polymers offer further advantages as to ease of synthesis, safety and improved resolution.
Abstract: A photocurable gel suitable for articles such as printing plates, photoresists and the like is disclosed. The photocurable gel comprises (a) a polymer composition having isotactic polymethyl methacrylate moiety; and syndiotactic polymethyl methacrylate moiety; (b) a photopolymerizable ethylenically unsaturated compound; and (c) a photopolymerization initiator. The gel is solid at ambient temperature and is capable of undergoing reversible gel/sol transition by heating or cooling. Methods of preparing articles, as well as methods of fixing articles, which use the gel are also disclosed. Such methods include sealing or affixing component parts on an electronic circuit board.
Abstract: A photopolymer useful in preparing water-developable, solid printing plates is prepared by (A) preparing a urethane prepolymer by reacting a polyoxyalkylene diol (optionally carboxylic acid grafted) with an excess of diisocyanate, followed by chain extending the resulting prepolymer mixture with a dialkylolpropionic acid and preferably with additional diols(s) such as alkane diol(s) and (meth)acrylate-containing diol(s). Use of a new (meth)acrylate-containing diol in such chain extension completes the formation of photopolymer. However, in a third operation (B) hydroxyalkylmethacrylate may be reacted with the result of (A) whether or not (meth)acrylate-containing diol is used in (A). The carboxylic acid groups of the photopolymer may also be partially neutralized with a base. The photopolymer is suitably formulated with additional photoactive (meth)acrylate monomers or oligomers and photoinitiator for casting on a substrate or extruding to form a flexographic printing plate.
Abstract: Flexographic photosensitive printing plates are made with formulations comprising triblock polymers of poly(vinylpyridine)-poly(butadiene) or poly(isoprene)-poly(vinylpyridine). The polymers may be quaternized or neutralized with an organic acid. When made with quaternized polymers, the plates after imaging with UV may be developed in aqueous solutions. The acid neutralized polymers offer further advantages as to ease of synthesis, safety and improved resolution.
Abstract: Novel polyurethane formulations especially useful as coating for the protection of ductile cast iron pipes. The polyurethane is prepared by mixing two components, A and B. Component A comprises castor oil, a low molecular weight polyol having a molecular weight between 76 and about 450, preferably with an elastomer. Component B is a polymeric MDI.
Abstract: A reactive plastisol composition includes a one component, solventless, storage stable, low temperature curable polyurethane composition and a thermoplast plastisol. The urethane composition is formed from a blocked isocyanate prepolymer and a curing agent. The isocyanate prepolymer is the reaction product of a polyol, a diisocyanate, and a ketoxime blocking agent. The diisocyanate has the formula ##STR1## in which R.sub.1 -R.sub.4 are each a C.sub.1 -C.sub.6 alkyl which can be linear or branched, R.sub.5 is a phenylene or naphthalene ring which is unsubstituted or substituted by one or more C.sub.1 -C.sub.12 linear or branched chained alkyl groups or halo groups, and m and n are each integers from 0 to 6. A polyurethane curing catalyst can also be used.
Type:
Grant
Filed:
May 1, 1991
Date of Patent:
February 8, 1994
Assignee:
W. R. Grace & Co.-Conn.
Inventors:
Truc-Chi T. Huynh-Tran, Felek Jachimowicz, Alexander C. Paton
Abstract: A method of preparing an unsaturated ester resin having improved storage stability is disclosed. An epoxy compound and polymerizable unsaturated monocarboxylic acid are reacted in the presence of a trivalent organic phosphorous catalyst. The catalyst is subsequently deactivated by oxidation. The resin may then be reacted with an acid anhydride.
Abstract: A photocurable composition P(Y)(Y.sub.1)(Y.sub.2) is prepared by reacting a solid carboxylated copolymer P(Y) having at least one pendent carboxyl group Y, and optionally one or more terminal carboxyl groups Y, with (i) a photosensitive vinyl-containing compound, e.g. glycidyl (meth)acrylate, which produces Y.sub.1 and optionally, with (ii) an anhydride, e.g. maleic anhydride, to produce Y.sub.2. Y.sub.1 has free vinyl groups and Y.sub.2 has free vinyl and acid groups. In addition, P(Y) can be a liquid carboxylated copolymer which is chain extended in order to prepare a solid. Either of the resulting photocurable compositions can be used "as is" or can be formulated with vinyl containing monomers and photoinitiators to prepare solid, flexible photosensitive articles, e.g. flexographic printing plates, which are water dispersible, and yet possess acceptable mechanical properties for flexographic printing.
Abstract: An improved asymmetric membrane fashioned from a polyimide for the liquid separation of solvents from lube oil. The membrane is based on a fully imidized polymer based on 5(6)-amino-1-(4'-aminophenyl)-1,3-trimethylindane polymer and benzophenone tetracarboxylic dianhydride.
Type:
Grant
Filed:
April 23, 1993
Date of Patent:
November 23, 1993
Assignee:
W. R. Grace & Co.-Conn.
Inventors:
Lloyd S. White, I-Fan Wang, Bhupender S. Minhas
Abstract: A dual curing composition is prepared from components consisting essentially of(a) an isocyanate adduct having (i) free isocyanate groups and (ii) free photopolymerizable ethylenically unsaturated groups, wherein the ethylenically unsaturated groups comprise in the range of 10 to 70% of the total of any free functional groups on said adduct;(b) reactive (meth)acrylate diluents; and(c) optionally, photoinitiator.When cured, the above composition is particularly suitable as a conformal coating on electronic circuit boards.
Abstract: Flexographic photosensitive printing plates are made with formulations comprising triblock polymers of poly(vinylpyridine)-poly(butadiene) or poly(isoprene)poly(vinylpyridine). The polymers may be quaternized. When made with quaternized polymers, the plates after imaging with UV may be developed in aqueous solutions.
Abstract: An epoxy composition suitable for adhesives, coatings and sealants is prepared from (a) at least one reaction product of an epoxy and amine-capped oligomer, (b) an epoxy adduct of dimer acid, (c) dicyandiamide and (d) a catalyst which yields a dimethyl amine radical upon being heated. When the epoxy composition is cured, it exhibits two glass transition temperatures and good adhesion properties at and below room temperature. The epoxy is particularly suitable for adhesives used in the manufacturing of automobiles.
Abstract: A method of initiating oxygen scavenging by compositions which comprise oxidizable organic compounds and transition metal catalysts is disclosed. The method comprises initiating scavenging by exposing the composition, etc., to radiation. The radiation exposure is preferably electron beam or ultraviolet light and is preferably used on oxygen scavenging compositions which comprise a substituted or unsubstituted ethylenically unsaturated hydrocarbon and a transition metal catalyst. Inclusion of a photoinitiator or antioxidant in the scavenging composition is also preferred to facilitate and/or control the composition's scavenging properties. The method can be used for initiating scavenging in packaging layers or articles for oxygen sensitive products such as food and beverage.
Type:
Grant
Filed:
June 27, 1991
Date of Patent:
May 18, 1993
Assignee:
W. R. Grace & Co.-Conn.
Inventors:
Drew V. Speer, William P. Roberts, Charles R. Morgan
Abstract: A tin catalyst constituting an organotin compound modified with an amine is used to catalyze the hydrolysis of latent amine curing agents in amine-curable polymeric compositions. The tin catalyst is formed from the reaction product of a stannous alkanoate and an amine, optionally in the form of an adduct with water. A preferred catalyst is the reaction product of stannous octoate and ethylenediamine.
Abstract: A tri-component polyimide copolymer and the process of preparing the copolymer are disclosed. A mixed reaction medium or solvent system comprising phenol and at least one compound of resorcinol, 1,6-dimethyl phenol and 4-methoxy phenol is used to produce the copolymer by direct imidization without isolating or purifying the imide oligomer as an intermediate.
Abstract: A polyimide resin composition with outstanding heat resistance and mechanical properties is disclosed, along with a novel method of its preparation. A tetracarboxylic acid or its derivative and an aromatic diamine are dissolved in a solvent system of mixed phenols and are both polymerized and imidized on one step.
Abstract: An adhesive composition for adhering two substrates includes a mixture of acrylate and epoxy with a tri- or tetrafunctional ketimine as a curing agent. The adhesive composition provides a two-stage cure in which, in a first stage, the adhesive is moisture cured at ambient temperature to provide green strength. In a second stage, the adhesive is post-cured at elevated temperatures to provide a high strength bond. The ketimine is formed form the reaction of diisopropyl ketone and an amine.
Abstract: The invention is directed to a process for preparing a sealant and adhesive useful, e.g., in double glazing systems. The sealant comprises 20-80 weight percent epoxidized natural rubber, 5-30 weight percent of at least one further epoxy compound, and, as a crosslinking agent, a polyamine or polymercaptan carrying trialkoxysilyl groups. The crosslinking agent is incorporated into the epoxidized natural rubber in one step.
Type:
Grant
Filed:
March 8, 1991
Date of Patent:
October 20, 1992
Assignee:
Teroson GmbH
Inventors:
Edward W. Duck, Karl Reich, Norman Blank
Abstract: A photocurable composition suitable for flexible photosensitive articles is prepared by reacting an acid-containing copolymer and a nitrogen-containing compound having polymerizable ethylenically unsaturated groups. The resulting composition can be used "as is" or can be formulated with ethylenically unsaturated monomers and photoinitiators to prepare the flexible photosensitive articles, e.g. flexographic printing plates. The plates prepared from the photocurable composition are aqueous developable and sufficiently flexible and soft to be used for printing on flexible packaging surfaces.