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JP-2026075914-A - Curable composition, cured product, and method for manufacturing a curable composition

JP2026075914AJP 2026075914 AJP2026075914 AJP 2026075914AJP-2026075914-A

Abstract

[Problem] To provide a curable composition that yields a cured product with good tensile strength, a cured product of the curable composition, and a method for manufacturing the curable composition. [Solution] A curable composition comprising polymer A and polymer B, wherein polymer A is an oxyalkylene polymer having two or more terminal groups in one molecule, the terminal groups not having a divalent organic group represented by -C(=O)NH-, and the terminal groups having at least one group selected from the group consisting of a specific reactive silicon group, an unsaturated group, and a hydroxyl group, and having a silylation rate of 85 to 100 mol%, and polymer B is an oxyalkylene polymer having two or more terminal groups in one molecule, the terminal groups having at least one group selected from the group consisting of a specific reactive silicon group, an isocyanate group, an amino group, and a hydroxyl group, and having a specific organic group. [Selection Diagram] None

Inventors

  • 金丸 明樹
  • 伊藤 高
  • ホ イング フ サムエル
  • 砂山 佳孝

Assignees

  • ＡＧＣ株式会社

Dates

Publication Date
20260511
Application Date
20241023

Claims (9)

  1. A curable composition comprising polymer A and polymer B, The polymer A is an oxyalkylene polymer having two or more terminal groups in one molecule, the terminal groups not having a divalent organic group represented by -C(=O)NH-, and the terminal groups having at least one group selected from the group consisting of a reactive silicon group, an unsaturated group, and a hydroxyl group represented by the following formula 1, and having a silylation rate of 85 to 100 mol% calculated by the following formula f1. The polymer B is a curable composition having two or more terminal groups in one molecule, and each terminal group has at least one group selected from the group consisting of a reactive silicon group represented by the following formula 1, an isocyanate group, an amino group, and a hydroxyl group, and is an oxyalkylene polymer having an organic group represented by the following formula i. -SiR a X 3-a formula 1 In formula 1, R is a monovalent organic group having 1 to 20 carbon atoms, excluding hydrolyzable groups; X is a hydroxyl group or a hydrolyzable group; and a is an integer from 0 to 2. When a is 2, R may be the same or different from each other; when a is 0 or 1, X may be the same or different from each other. The reactive silicon groups of polymer A and polymer B may be the same or different from each other. -C(=O)NH- Formula i
  2. The curable composition according to claim 1, wherein the number-average molecular weight of polymer A is 5,000 to 100,000.
  3. The curable composition according to claim 1, wherein the reactive silicon group of polymer A is a reactive silicon group represented by the following formula 3. -O-R 11 -SiR 12 a2 X 2 3-a2 Formula 3 In formula 3, R 11 is a linear alkylene group having 1 to 20 carbon atoms, and R 12 , X 2 , and a2 are the same as R, X, and a in formula 1, respectively. When a2 is 2, R 12 may be the same or different from each other, and when a2 is 0 or 1, X 2 may be the same or different from each other.
  4. The curable composition according to claim 1, wherein the number-average molecular weight of polymer B is 3,000 to 50,000.
  5. The curable composition according to claim 1, further comprising a curing catalyst, wherein the content of the curing catalyst is 0.01 to 20 parts by mass per 100 parts by mass of the total content of polymer A and polymer B.
  6. The curable composition according to claim 5, wherein the curing catalyst is a non-tin catalyst.
  7. A cured product of the curable composition according to any one of claims 1 to 6.
  8. A method for producing a curable composition according to any one of claims 1 to 6, Polymer A is obtained by reacting an unsaturated group-containing oxyalkylene polymer with a silylating agent in the presence of a group 8 metal catalyst and a co-catalyst containing either or both of a carboxylic acid compound having a carbon-carbon triple bond and a carboxylic acid compound having a carbon-carbon double bond at the α-carbon position. A method for producing a curable composition, comprising mixing polymer A and polymer B.
  9. The method for producing a curable composition according to claim 8, wherein the amount of silylation agent added is 0.85 to 1.50 molar times the total amount of unsaturated groups in the unsaturated group-containing oxyalkylene polymer.

Description

This invention relates to a curable composition, a cured product, and a method for producing a curable composition. Polymers containing at least one reactive silicon group per molecule are known to exhibit the property of crosslinking even at room temperature through the formation of siloxane bonds accompanied by hydrolysis reactions of the reactive silicon group due to moisture, etc., resulting in a rubbery cured product. Among these polymers containing reactive silicon groups, polymers with a main chain skeleton consisting of oxyalkylene polymers, saturated hydrocarbon polymers, alkyl acrylate polymers, and alkyl methacrylate polymers are already produced industrially and are widely used in applications such as sealants, adhesives, and paints. When curable compositions containing these polymers containing reactive silicon groups are used in the above applications, the tensile strength of the cured product is required. Cured products with excellent tensile strength are less prone to fracture. Patent Document 1 discloses a curable composition containing, in a specific proportion, an oxyalkylene polymer having three or more terminal groups in one molecule and a specific reactive silicon group having a number average molecular weight of 6000 or more per terminal group, and an oxyalkylene polymer having two or more terminal groups in one molecule and having an average of more than 0.5 and 1.0 trialkoxysilyl groups per terminal group. For example, Example 1 of Patent Document 1 describes a curable composition containing an oxyalkylene polymer having three terminal groups in one molecule, a number average molecular weight of 8000 per terminal group, and a methyldimethoxylyl group, and an oxyalkylene polymer having two terminal groups in one molecule and having a urethane bond and a trimethoxysilyl group. It is disclosed that the cured product of the above curable composition exhibits excellent curing speed, resilience of the cured product, conformability to the adherend, and elongation. International Publication No. 2020/066551 The meanings and definitions of terms used in this specification are as follows: A numerical range represented by "~" means a range of numbers whose lower and upper limits are the numbers before and after "~". The "units" that make up oxyalkylene polymers refer to atomic groups directly formed by the polymerization of alkylene oxide monomers. Oxyalkylene polymers are polymers consisting of a main chain containing polyoxyalkylene chains and terminal groups. In oxyalkylene polymers, the "main chain" refers to the portion (polyoxyalkylene chain) that includes residues obtained by removing active hydrogen from the initiator and repeating units based on alkylene oxide. In oxyalkylene polymers, the "end group" refers to the group of oxygen atoms in the polyoxyalkylene chain that is closest to the end of the molecule. However, if the group of oxygen atoms includes an initiator residue, it is not considered an end group but rather part of the main chain. An "active hydrogen-containing group" is at least one group selected from the group consisting of a hydroxyl group, carboxyl group, amino group, monovalent functional group obtained by removing one hydrogen atom from a primary amine, hydrazide group, and sulfanyl group, all of which are bonded to a carbon atom. "Active hydrogen" refers to hydrogen atoms based on the active hydrogen-containing group described above, and hydrogen atoms based on the hydroxyl group of water. An "unsaturated group" refers to a carbon-carbon double bond or a carbon-carbon triple bond. Carbon-carbon double bonds and carbon-carbon triple bonds may be located at the ends of the molecule or elsewhere. The number of terminal groups in an oxyalkylene polymer is the same as the number of active hydrogen atoms in the initiator, as will be discussed later. The "degree of unsaturation" can be measured according to the unsaturation measurement method (Wijs method). The degree of unsaturation indicates the proportion of carbon-carbon double bonds or carbon-carbon triple bonds in the polymer. The number-average molecular weight (Mn) and weight-average molecular weight (Mw) are polystyrene-equivalent molecular weights measured using GPC with tetrahydrofuran as the eluent, with a calibration curve created using polystyrene polymers of known molecular weight. The molecular weight distribution (Mw/Mn) is the ratio of Mw to Mn. The silylation rate can be measured by NMR analysis. A "silylation agent" refers to a compound having a functional group that reacts with a hydroxyl group, an unsaturated group, an isocyanate group, or an amino group, and a reactive silicon group. ≪Curable composition≫ The curable composition of this embodiment comprises the following polymer A and polymer B. Polymer A is an oxyalkylene polymer having two or more terminal groups in one molecule, the terminal groups not having a divalent organic group represented by -C(=O)NH-, but having at least one group selecte