Disclosed is an imine-type quaternary ammonium salt catalyst, wherein the catalyst has a general structure formula shown by formula I below; in the formula, R1 and R2, respectively, are independently selected from a C1-C20 linear alkyl or a branched C3-C20 alkyl, and a C1-C20 hydroxylalkyl, a C3-C8 cycloalkyl, and arylated alkyl; R3 is a linear or branched alkyl, cycloalkyl or aryl; and R4 is hydrogen, aryl, a linear C1-C15 alkyl or branched C3-C15 alkyl. Also disclosed are a method for preparing the catalyst and a polyisocyanate composition prepared therefrom. The catalyst, by introducing an imine structure, on the basis of ensuring high catalytic activity thereof, is allowed to have properties of high temperature decomposition and inactivation, and when applied to the synthesis of polyisocyanate, can effectively prevent the risk of explosive polymerization caused by an uncontrolled reaction.

The present invention provides a semicarbazide composition containing a semicarbazide compound (S) derived from an isocyanate compound (N) and a hydrazine, wherein the semicarbazide compound (S) has a hydrophilic functional group (a) and a structure (b) represented by the following formula (I), and a molar ratio (b)/(a) of the structure (b) to the hydrophilic functional group (a) is 0.1 or more and 10.0 or less, and the like.

##STR00001##

Provided herein are methods of recycling additively manufactured objects (e.g., stereolithographically produced objects), the additively manufactured objects comprising linear polyurethane, branched polyurethane, linear polyurea, branched polyurea, a copolymer thereof, or a combination thereof. Compositions comprising the same and methods of use thereof are also provided.

Disclosed is an imine-type quaternary ammonium salt catalyst, wherein the catalyst has a general structure formula shown by formula I below; in the formula, R1 and R2, respectively, are independently selected from a C1-C20 linear alkyl or a branched C3-C20 alkyl, and a C1-C20 hydroxylalkyl, a C3-C8 cycloalkyl, and arylated alkyl; R3 is a linear or branched alkyl, cycloalkyl or aryl; and R4 is hydrogen, aryl, a linear C1-C15 alkyl or branched C3-C15 alkyl. Also disclosed are a method for preparing the catalyst and a polyisocyanate composition prepared therefrom. The catalyst, by introducing an imine structure, on the basis of ensuring high catalytic activity thereof, is allowed to have properties of high temperature decomposition and inactivation, and when applied to the synthesis of polyisocyanate, can effectively prevent the risk of explosive polymerization caused by an uncontrolled reaction.

Disclosed are coated particles. The coated particles include substrate particles and a coating disposed over at least a portion of the substrate particles. The coating includes a condensation reaction product of a reaction mixture that includes a liquid isocyanate-functional component and an isocyanate-reactive composition. Also disclosed are methods for making such particles and methods for using such particles as proppants in hydraulic fracturing.

A two-component curable solventless-type laminate adhesive contains a polyisocyanate component and a polyol component. The polyisocyanate component contains a derivative of a pentamethylene diisocyanate, the derivative of the pentamethylene diisocyanate contains an isocyanurate group and an allophanate group, and the content ratio of the isocyanurate group with respect to 100 moles of the total amount of the isocyanurate group and the allophanate group is 60 moles or more and 99 moles or less.

A photopolymerizable composition including: a polymer matrix or a precursor thereof containing a reaction product of an acrylate-based polyol and a compound containing at least one isocyanate group; a photoreactive monomer; and a non-reactive fluoro compound and a photoinitiator; a hologram recording medium produced from the composition; an optical element including the hologram recording medium; and a method of recording a hologram using the photopolymerizable composition.

A developing roller having a rubber elastomer layer on the outer periphery of a shaft core metal, having a coating layer formed from a binder (A) and silicone rubber particles (B) on the surface of the rubber elastomer, and having an electrostatic capacitance of 4 to 20 nF; wherein the binder (A) is formed from a diluting solvent solution of a terminal hydroxyl group-containing prepolymer (a) obtained by reaction of an isocyanate compound, an isocyanurate modified product thereof and a reactive silicone oil, and an isocyanate compound and/or an isocyanurate modified product thereof (b). This developing roller suppresses banding by suppressing electrostatic capacitance even if the nip width between the developing roll and the photoreceptor changes due to distortion of peripheral members in the development apparatus, and stick slip (vibration) of gears.

A composition includes a capsules having an improved solvent and heat resistance. The capsules are prepared via interfacial polymerization between a polyisocyanate including at least one substituted or unsubstituted arylene or heterearyl group and a compound including an active hydrogen. The capsules include a leuco dye and may be used in laser markable compositions.

A photocatalyst according to the present invention has a structure in which the titanium dioxide doped with the transition metals is supported on the support such that a band gap thereof is low and a specific surface area thereof is high, thereby exhibiting an excellent photocatalytic activity even in a visible light region and providing an excellent effect of adsorbing an organic compound and removing the same even under a condition in which light is not emitted.