A curable perfluoropolyether adhesive composition containing the following components (A) to (C): (A) 100 parts by mass of a linear perfluoropolyether compound having at least two alkenyl groups per molecule and having a perfluoropolyether structure containing a repeating unit represented by —C.sub.aF.sub.2aO— in a main chain, “a” being an integer of 1 to 6; (B) an effective curing amount of an organosilicon compound having at least two silicon-bonded hydrogen atoms per molecule; and (C) a catalytic amount of a hydrosilylation-reaction catalyst, where a cured product of the curable perfluoropolyether adhesive composition is an adhesive having adhesion of less than 0.5 N/25 mm.

Reactive poly(fluoroalkyl-functional siloxane) oligomers, method of making the same, and compositions comprising the same are shown and described herein. The reactive poly(fluoroalkyl-functional siloxane) oligomers are is derived from a hydrolysable fluoroalkyl-functional silanes. Coating compositions comprising reactive poly(fluoroalkyl-functional siloxane) oligomer(s) may be used to form a coating or a film on a substrate and impart hydrophobic and/or oleophobic properties. The reactive poly(fluoroalkyl-functional siloxane) oligomer are more hydrophobic and oleophobic and show better chemical resistance than the hydrolysable fluoroalkyl-functional silane.

Reactive poly(fluoroalkyl-functional siloxane) oligomers, method of making the same, and compositions comprising the same are shown and described herein. The reactive poly(fluoroalkyl-functional siloxane) oligomers are is derived from a hydrolysable fluoroalkyl-functional silanes. Coating compositions comprising reactive poly(fluoroalkyl-functional siloxane) oligomer(s) may be used to form a coating or a film on a substrate and impart hydrophobic and/or oleophobic properties. The reactive poly(fluoroalkyl-functional siloxane) oligomer are more hydrophobic and oleophobic and show better chemical resistance than the hydrolysable fluoroalkyl-functional silane.

A room-temperature-curable organopolysiloxane composition; a structure obtained from the composition; and a method for assessing the cured state of the composition are provided. The room-temperature-curable organopolysiloxane composition, which changes in color with the progress of curing from the uncured state, comprises the following ingredients: (A) 100 parts by mass of one or more organopolysiloxanes represented by formula (1)
HO(SiR.sub.2O).sub.nH  (1)
and/or formula (2) ##STR00001##
(with variables as defined herein); (B) 0.1-50 parts by mass of an organosilicon compound having at least three silicon-atom-bonded hydrolyzable groups in the molecule, which is not any of ingredients (A), (C), and (D), and/or a product of the partial hydrolytic condensation of the organosilicon compound; (C) 0.01-20 parts by mass of a curing catalyst; (D) 0.1-10 parts by mass of a silane coupling agent; and (E) 0.01-10 parts by mass of a pH indicator.

A room-temperature-curable organopolysiloxane composition; a structure obtained from the composition; and a method for assessing the cured state of the composition are provided. The room-temperature-curable organopolysiloxane composition, which changes in color with the progress of curing from the uncured state, comprises the following ingredients: (A) 100 parts by mass of one or more organopolysiloxanes represented by formula (1)
HO(SiR.sub.2O).sub.nH  (1)
and/or formula (2) ##STR00001##
(with variables as defined herein); (B) 0.1-50 parts by mass of an organosilicon compound having at least three silicon-atom-bonded hydrolyzable groups in the molecule, which is not any of ingredients (A), (C), and (D), and/or a product of the partial hydrolytic condensation of the organosilicon compound; (C) 0.01-20 parts by mass of a curing catalyst; (D) 0.1-10 parts by mass of a silane coupling agent; and (E) 0.01-10 parts by mass of a pH indicator.

A modified polysiloxane has formula (I) ##STR00001##
In formula (I) m is an integer between 0 and 10000; n is an integer between 0 and 10000; m and n cannot be equal to 0 simultaneously; R.sub.1-R.sub.7 are the same or different; and at least one of R.sub.1-R.sub.7 includes a group having a reversible chemical bond system based on a hydrogen bond, a coordinate bond, or a covalent bond. The polysioxane is used as a main chain to introduce a reversible chemical bond having temperature sensitivity by using a chemical method, so as to obtain a polymer material which is highly sensitive to temperature. The temperature-sensitive properties of materials provide functional materials for specific applications, such as medical external fixation materials, orthopedic materials, and packaging materials, can be obtained by using particular processing and preparation methods.

A modified polysiloxane has formula (I) ##STR00001##
In formula (I) m is an integer between 0 and 10000; n is an integer between 0 and 10000; m and n cannot be equal to 0 simultaneously; R.sub.1-R.sub.7 are the same or different; and at least one of R.sub.1-R.sub.7 includes a group having a reversible chemical bond system based on a hydrogen bond, a coordinate bond, or a covalent bond. The polysioxane is used as a main chain to introduce a reversible chemical bond having temperature sensitivity by using a chemical method, so as to obtain a polymer material which is highly sensitive to temperature. The temperature-sensitive properties of materials provide functional materials for specific applications, such as medical external fixation materials, orthopedic materials, and packaging materials, can be obtained by using particular processing and preparation methods.

A method for producing a cyclic polysiloxane that includes a step for reacting a raw material cyclic siloxane and a dihalosilane in association with ring-opening of the cyclic siloxane in the presence of at least one catalyst selected from Lewis base compounds having a carbonamide bond represented by —C(═O)N<, phosphorus compounds having a P═O bond, quaternary ammonium salts, and quaternary phosphonium salts to obtain a linear polysiloxane with both ends of the molecular chain blocked by halogen atoms and a step for obtaining a cyclic polysiloxane by reacting the linear polysiloxane with both ends of the molecular chain blocked by halogen atoms with water makes it possible to provide a method for producing a cyclic polysiloxane that obtains a cyclic polysiloxane at high yield and high purity by simple steps and under moderate conditions.

A method for producing a cyclic polysiloxane that includes a step for reacting a raw material cyclic siloxane and a dihalosilane in association with ring-opening of the cyclic siloxane in the presence of at least one catalyst selected from Lewis base compounds having a carbonamide bond represented by —C(═O)N<, phosphorus compounds having a P═O bond, quaternary ammonium salts, and quaternary phosphonium salts to obtain a linear polysiloxane with both ends of the molecular chain blocked by halogen atoms and a step for obtaining a cyclic polysiloxane by reacting the linear polysiloxane with both ends of the molecular chain blocked by halogen atoms with water makes it possible to provide a method for producing a cyclic polysiloxane that obtains a cyclic polysiloxane at high yield and high purity by simple steps and under moderate conditions.

There is provided a curable composition for forming an anti-reflective film. The composition includes: (a) hollow silica nanoparticles; (b) a siloxane binder having reactive groups; (c) at least one additional material having reactive groups; (d) an initiator; and (e) solvent. The siloxane binder is present in an amount that is at least 50% by weight of the total weight of (siloxane binder+additional materials having reactive groups). The weight ratio of hollow silica nanoparticles to the total of (siloxane binder+additional materials having reactive groups) is no greater than 1.75 to 1.