摘要:
This invention relates to mixtures of polymethylene poly(phenylisocyanate) blends with epoxides. The addition of the epoxide stabilizes the reactivity of the polyisocyanate blends such that it is no longer dependent on the acidity. It is now possible to form polyurethanes from these mixtures based on polymethylene poly(phenylisocyanate) blends wherein less catalyst is necessary.
摘要:
The present invention relates to a method of making a coated substrate that requires a polyurethane/urea contact adhesive, and the coated substrates produced by this method. This invention requires a) a polyisocyanate with a functionality of less than about 4, b) optionally, a polyol blend consisting of about 95 to 100% polyether polyols with molecular weights from about 1800 to 12000 and average functionality from about 1.5 to about 4 and up to about 5% of chain extenders with molecular weights from about 60 to 400 and average functionality from about 1.5 to about 3, and c) polyethers having at least two isocyanate reactive groups and a molecular weight of from about 1800 to about 12000 and average functionality from about 1.5 to about 4 in which at least 50% of the isocyanate reactive groups are primary and/or secondary amino groups. The weight ratio of components b) to component c) ranges from about 95:5 to about 0:100, and the amounts of components a), b), and c) are such that the equivalent ratio of isocyanate groups to isocyanate-reactive groups is from about 85:100 to about 115:100 and the sum of the urethane group content plus the urea group content is from about 1 to about 12%.
摘要:
This invention relates to a process for the production of an optically clear, light-stable polyurethane-urea elastomer having an onset softening point of at least 130° C., processed at ambient temperature and casted in a mold at an isocyanate index of 95 to 120. This process comprises reacting: A) a liquid polyisocyanate or polyisocyanate prepolymer having an NCO group content of about 5 to about 50%, an average functionality of 2 to 3, a viscosity of less than 5,000 mPa.s at 25° C.; and B) an isocyanate-reactive component; in the presence of C) at least one organometallic catalyst. The present invention also relates to the optically clear, light-stable polyurethane-urea elastomers produced by this process.
摘要:
The present invention relates to highly elastic polyurethane contact adhesives, a process to coat substrates with these contact adhesives, and the coated substrates produced by this process. This invention requires a) a polyisocyanate with a functionality of less than about 4 and b) a polyol blend comprising 1) about 90 to 100% polyethers with molecular weights from about 1,800 to 12,000 and average functionality from about 1.5 to about 4, and 2) up to about 10% of chain extenders with molecular weights from about 60 to 400 and average functionality from about 1.5 to about 3. The functionalities and amounts of components a) and b) are such that the molecular weight between crosslinks is from about 7,000 to about 16,000 and the equivalent ratio of isocyanate groups to isocyanate-reactive groups is from about 80:100 to about 120:100 and the urethane group content is from about 1 to about 8%. It is preferred that at least one of components a) and b) have a functionality of greater than about 2.2.
摘要:
The present invention relates to highly elastic polyurethane contact adhesives, a process to coat substrates with these contact adhesives, and the coated substrates produced by this process. This invention requires a) a polyisocyanate with a functionality of less than about 4 and b) a polyol blend comprising 1) about 90 to 100% polyethers with molecular weights from about 1,800 to 12,000 and average functionality from about 1.5 to about 4, and 2) up to about 10% of chain extenders with molecular weights from about 60 to 400 and average functionality from about 1.5 to about 3. The functionalities and amounts of components a) and b) are such that the molecular weight between crosslinks is from about 7,000 to about 16,000 and the equivalent ratio of isocyanate groups to isocyanate-reactive groups is from about 80:100 to about 120:100 and the urethane group content is from about 1 to about 8%. It is preferred that at least one of components a) and b) have a functionality of greater than about 2.2.
摘要:
This invention relates to a process for the production of a polyurethane backing and air frothed foam on a substrate comprising the steps of a) mixing a polyisocyanate and a polyol blend in the presence of a catalyst to form a reaction mixture, b) applying the reaction mixture to a substrate, and c) curing the reaction mixture to form a polyurethane backing an/or an air frothed foam on the substrate. Suitable catalyst compositions for the present invention include those corresponding to the formula: ##STR1## wherein: each R: independently represents a linear or branched C.sub.1 to C.sub.24 (preferably from 5 to 16 carbon atoms and most preferably from 8 to 12 carbon atoms) alkyl group, or a cyclic group containing from 4 to 24 carbon atoms (preferably from 5 to 16 carbon atoms and most preferably from 8 to 12 carbon atoms).
摘要:
This invention relates to fertilizer encapsulation with polyurethanes wherein the isocyanate-reactive composition contains sulfur. The process of the present invention comprises applying a polyisocyanate composition to fertilizer particles, applying an isocyanate-reactive composition which contains sulfur to the polyisocyanate coated fertilizer particles, or applying an isocyanate-reactive composition which contains sulfur to fertilizer particles and then applying a polyisocyanate composition to the isocyanate-reactive coated fertilizer particles, and repeating these steps as necessary to form sulfur containing polyurethane encapsulated fertilizer particles.
摘要:
This invention relates to a process for the production of polyurea encapsulated fertilizer particles. These are produced by applying an isocyanate-reactive component which contains at least two amine groups to fertilizer particles to form amine coated particles, and applying a polyisocyanate component to the amine coated particles to form polyurea coated particles. These steps may optionally be repeated in successive order. The resultant polyurea encapsulated fertilizer particles contain from about 0.5 to 15% by weight of polyurea, based on the total weight of the encapsulated fertilizer particles. Instead of using an amine group containing isocyanate-reactive component, water can be applied first.
摘要:
A method for supply chain design may include identifying nodes, links connecting the nodes, and replenishment strategies for moving materials along the links, in a supply chain. The method may also include determining a value indicative of the complexity of the supply chain based on a characteristic of the nodes, links, and replenishment strategies. The method may also include identifying whether core competencies of the nodes are underutilized. The method may also include reducing the complexity of the supply chain to increase utilization of the core competencies of the nodes.
摘要:
A method for supply chain design may include identifying nodes, links connecting the nodes, and replenishment strategies for moving materials along the links, in a supply chain. The method may also include determining a value indicative of the complexity of the supply chain based on a characteristic of the nodes, links, and replenishment strategies. The method may also include identifying whether core competencies of the nodes are underutilized. The method may also include reducing the complexity of the supply chain to increase utilization of the core competencies of the nodes.