The present invention particularly relates to synthesizing photo-initiators having poly-oligo-silsesquioxane (POSS) structure and realizing photo-polymerization by using these photo-initiators and simultaneous and in-situ synthesis of Ag nano-particles in polymer matrix comprising POSS structure and obtaining wrinkled surfaces as a result of self-arranging thereof.

Diterminally silanol-modified perfluoropolyether compounds of the general formula (1)

##STR00001##

(wherein each R.sup.1 is independently an unsubstituted divalent hydrocarbon group of 1 to 10 carbon atoms, each R.sup.2 is independently a substituted or unsubstituted monovalent hydrocarbon group of 1 to 10 carbon atoms, Rf is a perfluoropolyether group, and ‘n’ is independently at each occurrence an integer from 0 to 8) are provided. Such compounds, when reacted as an intermediate with a reactive silicon compound, afford compounds of excellent durability.

Diterminally silanol-modified perfluoropolyether compounds of the general formula (1) ##STR00001##
(wherein each R.sup.1 is independently an unsubstituted divalent hydrocarbon group of 1 to 10 carbon atoms, each R.sup.2 is independently a substituted or unsubstituted monovalent hydrocarbon group of 1 to 10 carbon atoms, Rf is a perfluoropolyether group, and ‘n’ is independently at each occurrence an integer from 0 to 8) are provided. Such compounds, when reacted as an intermediate with a reactive silicon compound, afford compounds of excellent durability.

Reaction system for preparing acetoxy function-bearing siloxanes having chain lengths of more than 3 silicon atoms, comprising silanes and/or siloxanes bearing alkoxy groups, silanes and/or siloxanes bearing acetoxy groups, silanes and/or siloxanes bearing hydroxy groups and/or simple siloxane cycles and/or DT cycles, and also a reaction medium comprising acetic anhydride, Brønsted acid and acetic acid, wherein Brønsted acids having a pKa ≤−1.30 are used, and wherein the acetic acid is present in the reaction system in amounts of 0.4 to 15.0 percent by weight, based on the reaction system, wherein the molar ratio of Brønsted acid used to acetic acid is in a defined range, with the proviso that either the sole use of trifluoromethanesulfonic acid and also of trifluoromethanesulfonic acid and acetic acid is excluded, and/or that the Brønsted acid used at least in part has a pKa between −1.3 and >−13.5.

The present invention particularly relates to synthesizing photo-initiators having poly-oligo-silsesquioxane (POSS) structure and realizing photo-polymerization by using these photo-initiators and simultaneous and in-situ synthesis of Ag nano-particles in polymer matrix comprising POSS structure and obtaining wrinkled surfaces as a result of self-arranging thereof.

Reaction system for preparing acetoxy function-bearing siloxanes having chain lengths of more than 3 silicon atoms, comprising silanes and/or siloxanes bearing alkoxy groups, silanes and/or siloxanes bearing acetoxy groups, silanes and/or siloxanes bearing hydroxy groups and/or simple siloxane cycles and/or DT cycles, and also a reaction medium comprising acetic anhydride, Brnsted acid and acetic acid, wherein Brnsted acids having a pKa 1.30 are used, and wherein the acetic acid is present in the reaction system in amounts of 0.4 to 15.0 percent by weight, based on the reaction system, wherein the molar ratio of Brnsted acid used to acetic acid is in a defined range, with the proviso that either the sole use of trifluoromethanesulfonic acid and also of trifluoromethanesulfonic acid and acetic acid is excluded, and/or that the Brnsted acid used at least in part has a pKa between 1.3 and >13.5.

Mixtures of cyclic branched siloxanes having exclusively D and T units, with the proviso that the cumulative proportion of the D and T units having Si-alkoxy and/or SiOH groups that are present in the siloxane matrix, determinable by .sup.29Si NMR spectroscopy, is less than 2.0 and preferably less than 1.0 mole percent, are described, as are branched organomodified siloxanes obtainable therefrom.

An object of the present invention is to provide a monomer having a polysiloxane structure and capable of providing a polymer having sufficient compatibility and hydrolysis resistance while having high oxygen permeability useful for an ophthalmic device, and a method for producing the monomer.

The present invention provides a siloxane compound represented by the formula (1) which has a radical-polymerizable group at one terminal and an alkyl group having 1 to 10 carbon atoms at the other terminal, and has a divalent hydrocarbon group L which has 2 to 20 carbon atoms and may contain one or more selected from an ether bond and a urethane bond, wherein a part of hydrogen atoms bonded to the carbon atoms may be substituted with a hydroxyl group. The siloxane compound further has a hydrophilic group represented by formula (3) bonded to a silicon atom in the siloxane chain.

An aqueous coating material is provided. The aqueous coating material includes an aqueous resin and a surfactant. The surfactant having a hydrophilic segment of poly(alkylene glycol), a hydrophobic segment of siloxane, and a terminal hydrophilic group. The aqueous resin and the surfactant may have a weight ratio of 100:1 to 100:25.

A transformed metal oxide sol, according to the present invention, has as main components: a hydrolysis product of a surface-active silane coupling agent, a transformed metal oxide sol which has been transformed by means of a hydrolysis product of a surface-active silane coupling agent, or a mixture and/or a condensate of the hydrolysis product of the surface-active silane coupling agent and the transformed metal oxide sol which has been transformed by means of the hydrolysis product of the surface-active silane coupling agent; and a mixture of transformed metal oxide sols which have been transformed by means of sulfur-containing functional groups, wherein a raw metal oxide sol of the transformed metal oxide sol is preferably an organosilica sol.