Methods in which toughness improvers based on terminally blocked polyurethane prepolymers are used to increase the maximum linear expansion of single component heat-curing epoxy resin compositions, in particular for joining substrates having different thermal expansion coefficients, in particular in the framework of transport agents or white goods.

Process for preparing rigid polyurethane or urethane-modified polyisocyanurate foams from polyisocyanates and polyfunctional isocyanate-reactive compounds in the presence of blowing agents wherein the polyfunctional isocyanate-reactive compounds comprise an unmodified or modified novolac polyol and a polyether polyol having a hydroxyl number of between 50 and 650 mg KOH/g obtained by reacting a polyfunctional initiator first with ethylene oxide and subsequently with propylene oxide wherein the propoxylation degree is between 0.33 and 2 mole propylene oxide per active hydrogen atom in the initiator and wherein the molar ratio of ethylene oxide to propylene oxide in said polyether polyol is at least 2.

A reaction system for forming a viscoelastic polyurethane foam includes an isocyanate component that has at least one isocyanate and an isocyanate-reactive component that is a mixture formed by adding at least a polyol component, an additive component, and a preformed aqueous polymer dispersion. The mixture includes, based on the total weight of the mixture, from 50.0 wt % to 99.8 wt % of a polyol component including at least one polyether polyol, from 0.1 wt % to 50.0 wt % of an additive component including at least one catalyst, and from 0.1 wt % to 6.0 wt % of a preformed aqueous polymer dispersion. The preformed aqueous polymer dispersion has a solids content from 10 wt % to 80 wt %, based on the total weight of the preformed aqueous polymer dispersion, and is one of an aqueous acid polymer dispersion or an aqueous acid modified polyolefin polymer dispersion in which the polyolefin is derived from at least one C.sub.2 to C.sub.20 alpha-olefin.

A resin composition for the secondary coating of an optical fiber is a resin composition containing a non-reactive urethane compound having a number average molecular weight of 10000 or more and 50000 or less, a photopolymerizable compound, and a photopolymerization initiator, the content of the non-reactive urethane compound is 0.05 parts by mass or more and 5 parts by mass or less based on the total amount of the resin composition, and the non-reactive urethane compound is a reaction product of a polyol having a number average molecular weight of 8000 or more and 20000 or less, a diisocyanate, and a compound having active hydrogen.

There is provided a two-part urethane adhesive composition including: a main agent containing a polyisocyanate component (A); and a curing agent containing water and an active hydrogen-containing compound (B). The (B) contains a compound represented by Formula (4); the (A) contains a urethane prepolymer (A-3); an average active hydrogen concentration of the (B) is 0.50 to 3.50 mol/kg; an average active hydrogen concentration of the (B) and the water is 2.00 to 8.00 mol/kg. The main agent and the curing agent are mixed in such amounts as to satisfy conditions that: a ratio of the number of isocyanate groups of the (A) to the number of active hydrogens of the (B) is 1 to 5; and a ratio of the number of isocyanate groups of the (A) to the total number of active hydrogens of the (B) and the water is 0.5 to 2.5.

Thixotropic polyol dispersions are described. The dispersions contain a dispersed phase of polyurethane-isocyanurate particles. They can be made by reacting a low equivalent weight polyol with a polyisocyanate in the presence of an isocyanate trimerization catalyst while dispersed in a base polyol. These polyol dispersions are useful as the resin component of curable systems such as formulated coatings, sealants or adhesives.

A crosslinkable composition is useful for preparing a skin contact adhesive or a coating on a substrate. The crosslinkable composition includes (A) a polyurethane-polyorganosiloxane copolymer and (B) a curing catalyst. The skin contact adhesive prepared by crosslinking the crosslinkable composition is useful in applications such as adhesives for medical tapes, adhesives for wound dressings, adhesives for prosthetics, ostomy appliance adhesives, adhesives for medical monitoring appliances, adhesives for scar therapy treatments, adhesives for cosmetic patches, and transdermal drug delivery systems.

The invention relates to a process for preparing a polyoxyalkylene carbonate polyol by reacting a polyoxyalkylene polyol with a cyclic carbonate in the presence of an amine catalyst. The invention further relates to polyoxyalkylene carbonate polyols obtainable using the method according to the invention and to a process for preparing polyurethanes by reacting the polyoxyalkylene carbonate polyols according to the invention with polyisocyanates.

The present invention relates to a polyurethane (PP2) comprising at least two, preferably two or three, end functional groups T of following formula (I):

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The present invention also relates to the uses of the polyurethanes (PP2) for the preparation of multicomponent systems.

The present invention relates to radiation of dual radiation/moisture curable compositions based on (meth)acrylate- and silane-terminated polymers that can be used as 3D printing materials and provide isotropic and elastomeric properties. The invention further relates to the use thereof as 3D printing materials and printing methods using said compositions.