The present disclosure belongs to the field of organic synthesis, and particularly relates to a ring-opening polymerization method for a cyclic monomer. A specific solution is that a Lewis acid-base pair is used to catalyze ring-opening polymerization of the cyclic monomer in the presence of an initiator. By using the Lewis acid-base pair as a catalyst, on one hand, a range of a ring-opening polymerization catalyst is widened, and on the other hand, this catalyst achieves a higher catalytic efficiency and is milder in comparison with previously reported strong acid or strong base catalysts. In addition, through a bifunctional activation mechanism, this catalyst system activates the monomer and simultaneously activates the initiator or a chain end, and has the characteristics of high efficiency in comparison with the reported monomer activation mechanism or chain end activation mechanism. By adopting the catalyst, a polyester product with a target molecular weight can be synthesized in a controlled manner as required, with a narrower molecular weight distribution index, a high product yield, a high product conversion rate and no monomer or metal residues.

A polyalkylene glycol-based compound of formula (1):

##STR00001##

may be one in which R.sup.1 is a monovalent hydrocarbon group having 1 to 32 carbon atoms, a monovalent aromatic hydrocarbon group having 6 to 42 ring carbon atoms, a monovalent acyl group having 2 to 32 carbon atoms, or a monovalent oxygen-containing hydrocarbon group having 2 to 32 carbon atoms; R.sup.2 is a monovalent hydrocarbon group having 1 to 32 carbon atoms, a monovalent aromatic hydrocarbon group having 6 to 42 ring carbon atoms, a monovalent acyl group having 2 to 32 carbon atoms, a monovalent oxygen-containing hydrocarbon group having 2 to 32 carbon atoms, or a hydrogen atom; R.sup.3 is a divalent hydrocarbon group having 4 carbon atoms; R.sup.4 is a divalent hydrocarbon group having 2 or 3 carbon atoms; m and n are respectively numbers between 1 and 40 and 0 and 20; and m/(m+n)≥0.5.

A polyalkylene glycol-based compound may have formula (1):

##STR00001##

wherein R.sup.1 is a monovalent aromatic hydrocarbon group having 6 to 42 ring carbon atoms; R.sup.2 is a monovalent aromatic hydrocarbon group having 6 to 42 carbon atoms or a hydrogen atom; R.sup.3 is a divalent hydrocarbon group having 2 to 4 carbon atoms; and m is a number in a range of from 1 to 40.

A polyalkylene glycol-based compound may have formula (1):

##STR00001##

wherein R.sup.1 is a monovalent aromatic hydrocarbon group having 6 to 42 ring carbon atoms; R.sup.2 is a monovalent aromatic hydrocarbon group having 6 to 42 carbon atoms or a hydrogen atom; R.sup.3 is a divalent hydrocarbon group having 2 to 4 carbon atoms; and m is a number in a range of from 1 to 40.

A surface-treating agent including a perfluoro(poly)ether group-containing silane compound and a perfluoro(poly)ether group-containing compound. The perfluoro(poly)ether group-containing compound contains a radical capturing group or a UV absorbing group in the molecule.

The invention relates to a curable composition comprising: a) at least one polymer having at least one silicon-containing group of formula —Si(R.sup.1).sub.k(Y).sub.3-k as defined herein, and b) at least one hydroxyl-functionalized polysiloxane polyalkyleneglycol brush copolymer of the structure [A(-X—B)].sub.s as defined herein; and an adhesive, sealant, or coating material comprising said curable composition and use thereof.

The invention relates to a curable composition comprising: a) at least one polymer having at least one silicon-containing group of formula —Si(R.sup.1).sub.k(Y).sub.3-k as defined herein, and b) at least one hydroxyl-functionalized polysiloxane polyalkyleneglycol brush copolymer of the structure [A(-X—B)].sub.s as defined herein; and an adhesive, sealant, or coating material comprising said curable composition and use thereof.

The present invention provides a polyrotaxane having high durability and in particular, high hydrolysis resistance, and a method for producing said polyrotaxane. The present invention provides a polyrotaxane obtained by disposing blocking groups on both ends of a pseudopolyrotaxane so that an annular molecule cannot be displaced, said pseudopolyrotaxane being obtained by forming a clathrate by piercing the opening of the cyclic molecule with a linear molecule, said polyrotaxane being characterized in that the cyclic molecule has a substituent represented by formula I (in formula I, R.sub.1 represents a group such as —CH.sub.3 and —CH.sub.2—CH.sub.3, R.sub.2 represents H or a group such as —CH.sub.3, and n is the apparent degree of polymerization of a polyalkylene oxide chain or a derivative thereof added to the cyclic molecule, the value of n being 1.1 to 10.0).

A toughened epoxy resin composition includes an end-capped polyalkylene oxide (A), an epoxy resin (B), an epoxy curing agent (C), and a core shell polymer (D). The end-capped polyalkylene oxide (A) has a number average molecular weight of 1500 to 5000, and 40% or more of a total number of ends of the end-capped polyalkylene oxide (A) are capped with at least one selected from the group consisting of an alkyl group, an allyl group, and an aryl group. A weight ratio of the end-capped polyalkylene oxide (A) to the core shell polymer (D) is 10/90 to 90/10. The core shell polymer (D) comprises a core layer in an amount of 70 to 95% by weight and the core layer is one or more selected from the group consisting of diene rubber, (meth)acrylate rubber, organosiloxane rubber, styrene polymer, and (meth)acrylate polymer.

A toughened epoxy resin composition includes an end-capped polyalkylene oxide (A), an epoxy resin (B), an epoxy curing agent (C), and a core shell polymer (D). The end-capped polyalkylene oxide (A) has a number average molecular weight of 1500 to 5000, and 40% or more of a total number of ends of the end-capped polyalkylene oxide (A) are capped with at least one selected from the group consisting of an alkyl group, an allyl group, and an aryl group. A weight ratio of the end-capped polyalkylene oxide (A) to the core shell polymer (D) is 10/90 to 90/10. The core shell polymer (D) comprises a core layer in an amount of 70 to 95% by weight and the core layer is one or more selected from the group consisting of diene rubber, (meth)acrylate rubber, organosiloxane rubber, styrene polymer, and (meth)acrylate polymer.