A belt for power transmission or transport comprising a polyurethane belt body, wherein the polyurethane of the belt body is the reaction product of a urethane prepolymer and a diamine chain extender, and the urethane prepolymer is based on a polyether and a linear aliphatic diisocyanate. The belt has excellent hydrolysis resistance.

The present disclosure is to provide a polishing pad which is capable of providing physical properties corresponding to various polishing purposes for various polishing objects through the subdivided structural design in a thickness direction, and of securing environmental friendliness by applying a recycled or recyclable material to at least some components, in relation to disposal after use, unlike the conventional polishing pad. Specifically, the polishing pad includes a polishing layer, wherein the polishing layer includes a polishing variable layer having a polishing surface; and a polishing constant layer disposed on a rear surface side of the polishing variable layer opposite to the polishing surface, and wherein the polishing constant layer includes a cured product of a composition having thermosetting polyurethane particles and a binder.

The present disclosure is to provide a polishing pad which is capable of providing physical properties corresponding to various polishing purposes for various polishing objects through the subdivided structural design in a thickness direction, and of securing environmental friendliness by applying a recycled or recyclable material to at least some components, in relation to disposal after use, unlike the conventional polishing pad. Specifically, the polishing pad includes a polishing layer, wherein the polishing layer includes a polishing variable layer having a polishing surface; and a polishing constant layer disposed on a rear surface side of the polishing variable layer opposite to the polishing surface, and wherein the polishing constant layer includes a cured product of a composition having thermosetting polyurethane particles and a binder.

A chemical mechanical polishing pad for polishing a semiconductor substrate is provided containing a polishing layer that comprises a polyurethane reaction product of a reaction mixture comprising (i) one or more diisocyanate, polyisocyanate or polyisocyanate prepolymer, (ii) from 40 to 85 wt. % based on the total weight of (i) and (ii) of one or more blocked diisocyanate, polyisocyanate or polyisocyanate prepolymer which contains a blocking agent and has a deblocking temperature of from 80 to 160° C., and (iii) one or more aromatic diamine curative. The reaction mixture has a gel time at 80° C. and a pressure of 101 kPa of from 2 to 15 minutes; the polyurethane reaction product has a residual blocking agent content of 2 wt. % or less; and the polishing layer exhibits a density of from 0.6 to 1.2 g/cm.sup.3.

A chemical mechanical polishing pad for polishing a semiconductor substrate is provided containing a polishing layer that comprises a polyurethane reaction product of a reaction mixture comprising (i) one or more diisocyanate, polyisocyanate or polyisocyanate prepolymer, (ii) from 40 to 85 wt. % based on the total weight of (i) and (ii) of one or more blocked diisocyanate, polyisocyanate or polyisocyanate prepolymer which contains a blocking agent and has a deblocking temperature of from 80 to 160° C., and (iii) one or more aromatic diamine curative. The reaction mixture has a gel time at 80° C. and a pressure of 101 kPa of from 2 to 15 minutes; the polyurethane reaction product has a residual blocking agent content of 2 wt. % or less; and the polishing layer exhibits a density of from 0.6 to 1.2 g/cm.sup.3.

A polyurea composition containing monomeric diisocyanates in an amount of max. 0.5 wt.% and consisting of a first component containing a primary, aromatic diamine and a second component containing an isocyante-group-containing polyether urethane polymer containing monomeric diisocyantes in an amount of max. 0.5 wt.% and an aliphatic polyisocyanate with an NCO content of 8 to 25 wt.%.

Silicone polyurea block copolymers are prepared by copolymerizing: (a) a diamine composition that includes a polyethylene glycol diamine, and optionally, a dipiperidyl alkane; (b) a monofunctional silicone isocyanate; and (c) a diisocyanate. Compositions useful as passivating coatings comprising the block copolymer are also provided, and substrates coated with the compositions. Methods of preparing and using the compositions are also described.

A molding method for producing a screw drill stator using an elastomer material includes: S1. sequentially roughening, cleaning and drying an inner surface of the stator tube; mixing an adhesive and a diluent, coating the mixture obtained on the inner surface, and heating it for later use; S2, uniformly coating a mold release agent on a surface of a mandrel mold, and heating or drying it naturally for later use; S3. assembling the processed stator tube and the processed mandrel mold to obtain an assembled mold; S4. performing a vacuum defoaming under negative pressure on a mixture obtained by uniformly mixing a prepolymer of the elastomer material with a defoaming agent; S5. uniformly mixing the defoamed prepolymer of the elastomer material with a curing agent, and pouring the obtained mixture into the assembled mold, sealing and curing the poured assembled mold by hierarchical heating to obtain the stator.

A molding method for producing a screw drill stator using an elastomer material includes: S1. sequentially roughening, cleaning and drying an inner surface of the stator tube; mixing an adhesive and a diluent, coating the mixture obtained on the inner surface, and heating it for later use; S2, uniformly coating a mold release agent on a surface of a mandrel mold, and heating or drying it naturally for later use; S3. assembling the processed stator tube and the processed mandrel mold to obtain an assembled mold; S4. performing a vacuum defoaming under negative pressure on a mixture obtained by uniformly mixing a prepolymer of the elastomer material with a defoaming agent; S5. uniformly mixing the defoamed prepolymer of the elastomer material with a curing agent, and pouring the obtained mixture into the assembled mold, sealing and curing the poured assembled mold by hierarchical heating to obtain the stator.

A method for operation in wellbore, the method comprises: pumping a fluid barrier into a wellbore through a tubular, the fluid barrier being operable to separate a cement slurry from a second fluid; the fluid barrier comprising a polyurethane member derived from a polyurethane forming composition comprising a para-phenylene diisocyanate terminated polycarbonate prepolymer and an aromatic diol.