JPH0248010B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a novel polyamide/polysiloxane block copolymer.
More specifically, the present invention relates to a method for producing a novel polyamide/polysiloxane block copolymer obtained by bonding a polyamide polymer and a polysiloxane polymer through urethane bonds.

In recent years, resins or resin mixtures containing polysiloxane polymers have attracted attention. As is well known, polysiloxane polymers have excellent physicochemical properties such as heat resistance and cold resistance, so they can be used for primary products such as rubber (silicone rubber), oil, and varnish, as well as for various secondary products using them as raw materials. is put into practical use. Furthermore, in recent years, research has been conducted in a wide variety of fields to develop various functions of polysiloxane polymers while maintaining the above-mentioned physicochemical properties. For example, in the field of engineering plastics, research has been conducted to utilize the low-temperature elasticity of plastics to create tubes and hoses with high resistance to low-temperature shock, while in the field of medical materials, the biochemical stability of plastics has been utilized to create orthopedic materials, blood vessels, etc. Many products have already been put into practical use as prosthetic materials, ointment base materials, etc. Furthermore, its usefulness is attracting attention in the field of gas separation membranes from the standpoint of resource and energy conservation. The gas separations targeted here include the separation and purification of recycled gases such as helium purification, rare gas separation, uranium enrichment, oxygen enrichment, ethanol synthesis, and acetic acid synthesis. It has been put into practical use because of its improved efficiency.

Methods for producing resins or resin mixtures containing polysiloxane polymers include the following.

(1) A method of directly kneading a polysiloxane polymer with other resins is described, for example, in JP-A-58-93749, Plastics.
It is described in World p.70 March, 1983, etc.

(2) Methods for producing block copolymers by chemically combining polysiloxane polymers with other polymers such as polyesters, polyethers, polyurethanes, and polycarbonates include, for example, WL
Roff, Ann.NYAcd.Sci., 146, 119 (1967),
It is described in WJ Ward, J.Mom.Sci., 1, USP3781378, etc.

(3) A method of graft polymerizing polysiloxane to a suitable backbone polymer is described, for example, in JP-A-57-135007;
Described in Proceedings of the Society of Polymer Science 31 , 461 (1982).

(4) A method of synthesizing a polymer by anionic polymerization of a polymerizable group containing polysiloxane as a substituent in the side chain is described, for example, in Japanese Patent Publication No. 52-21021.

Among the various manufacturing methods mentioned above, polysiloxane (2) above is the most suitable manufacturing method for developing mechanical, electrical, and physical properties depending on the use of the resin, from the viewpoint of ease of molecular design. It is thought that this method involves chemically combining a polymer with another polymer to obtain a block copolymer.

As a result of intensive research, the present inventors have found that by combining polyamide polymers and polysiloxane polymers with appropriate urethane bonds, mechanical strength, abrasion resistance, gasoline resistance, lubricant resistance, etc. can be improved. The present invention was achieved by discovering a method for obtaining a new polyamide/polysiloxane block copolymer that maintains the excellent properties of polyamide resin while also imparting heat resistance, water absorption resistance, and chemical resistance. .

That is, the present invention is obtained by polycondensation of a lactam or α,ω-amino acid having a hydrocarbon chain of 2 to 15 carbon atoms, or a dicarboxylic acid and a diamine having a hydrocarbon chain of 2 to 15 carbon atoms, and Number average molecular weight 500~ with carboxyl group or amino group at both ends
10,000 both-terminated dicarboxylic acid polyamide or both-terminated diamine polyamide and the following general formula (1), (2) or
(3) One or more polysiloxanes selected from polysiloxanes having a number average molecular weight of 200 to 20,000 and having hydroxyl groups, amino groups, or carboxyl groups at both ends, and two isocyanate groups. This is a method for producing a polyamide/polysiloxane block copolymer, characterized in that the polyamide/polysiloxane block copolymer is bonded by a compound having the following properties.

(M is alkylene group, phenylene group or oxyethylene group, R is H, CH ₃ or phenyl group, n=0
~50, t=0~5) (M, R are the same as formula (1), n = 0 ~ 50, p = 0 ~
5) (M, R are the same as formula (1), n = 0 ~ 50, q = 0 ~
5) The dicarboxylic acid polyamide or diamine polyamide whose both ends are carboxyl groups or amino groups used in the present invention can be obtained by a known method. That is, the above polycondensation reaction is carried out in the presence of a dicarboxylic acid or an organic diamine (these functional groups are preferably located at the ends of the hydrocarbon chain). These dicarboxylic acids or diamines are combined during the polycondensation reaction to form polymeric polyamide chain moieties. Furthermore, a dicarboxylic acid group or a diamine group can be added to the end of the chain to obtain an α,ω-dicarboxylic acid polyamide or an α,ω-diamine polyamide. Further, these dicarboxylic acids and diamines act as chain regulators. For this purpose, dicarboxylic acid polyamides of a given molecular weight,
The α,ω-dicarboxylic acid and α,ω-diamine are used in excess of the amount required to obtain the diamine polyamide. By appropriately selecting this excess ratio, the length of the polymer chain, that is, the average molecular weight of the polyamide can be adjusted.

Specific methods of the production method of the present invention include (1) a method in which polyamide is first reacted with a compound having two isocyanate groups and then reacted with polysiloxane to obtain a polyamide/polysiloxane block copolymer; (2) There is a method in which polysiloxane is first reacted with a compound having two isocyanate groups and then reacted with polyamide to obtain a polyamide/polysiloxane block copolymer. Both methods yield similar polyamide/polysiloxane block copolymers. Therefore, the method (1) above will be explained below as a typical example, but the method (2) can also be implemented in the same way.

The polyamide used in the present invention is a lactam whose hydrocarbon chain has 2 to 15 carbon atoms or α,ω-
Amino acids such as caprolactam, enantholactam, dodecalactam, undecanolactam, dodecanolactam, 11-amino-undecanoic acid, 12
-Aminododecanoic acid, etc. can be used as a starting material.

Polyamides used in the present invention include condensation products of dicarboxylic acids and diamines, such as condensation products of hexamethylenediamine and adipic acid, azelaic acid, sebacic acid, or 1,12-dodecanedioic acid, and nonamethylene. Nylon 6-6, 6-9, which is a condensation product of diamine and adipic acid,
6-10, 6-12, 9-6, etc. may also be mentioned.

Dicarboxylic acids and organic diamines used as chain regulators in polyamide synthesis reactions make it possible to obtain polyamides having carboxyl groups or amino groups at both ends; Group dicarboxylic acids are preferred, and the diamines have 5 to 14 carbon atoms.
Preferred are aliphatic diamines.

Alicyclic or aromatic dicarboxylic acids, diamines can also be used. These dicarboxylic acids and diamines are used in amounts that are in excess of the amount necessary to obtain a polyamide having a desired average molecular weight, according to known calculation methods currently used in the field of polycondensation reactions.

Dicarboxylic acid polyamide used in the present invention,
The average molecular weight of diamine polyamide is 500-10000,
Preferably it is 800-5000.

The diisocyanate compound having an isocyanate group at the chain end used in the present invention may be either linear or branched, and is not limited to aliphatic, but may also be alicyclic or aromatic. For example, tetramethylene diisocyanate, hexamethylene diisocyanate, octamethylene diisocyanate,
These include nonamethylene diisocyanate, dodecamethylene diisocyanate, 2,4-tolylene diisocyanate, diphenylmethylene diisocyanate, and the like. The average molecular weight of such polymethylene diisocyanates is from 50 to 8000, preferably from 100 to
5000. The above diisocyanate compound can be used in an amount of equimolar to twice the molar amount of the dicarboxylic acid polyamide or diamine polyamide, but since the isocyanate group is active toward amino groups (primary amino group , the reaction activity decreases in the order of secondary amino groups), and it is desirable to carry out the reaction at low temperatures to avoid side reactions.

The catalyst used in the reaction between polyamide and diisocyanate compound is suitably a tertiary amine or a heavy metal derivative, such as diazabicyclooctane or its derivative diazabicycloundecene, dibutyltin dilaurylate, zinc dilaurylate, Examples include lead dilaurylate. Such a catalyst is hardly needed when diamine polyamide and a diisocyanate compound are reacted, and the reaction is sufficiently rapid even without a catalyst, but there is no problem in adding it. That is, in the reaction of dicarboxylic acid polyamide or diamine polyamide with a diisocyanate compound, the above-mentioned catalyst alone or together with an alkali metal or alkaline earth metal alcoholate is used in an amount of 0.01 to 2% by weight, preferably 0.01 to 2% by weight of the total amount of the reaction mixture. It can be used in amounts of 0.03 to 1% by weight.

In the presence of the above catalyst, polysiloxanes having various functional groups as shown in the above formula (1), (2) or (3) are added as soft segments to the terminal diisocyanate polyamide urethane synthesized as above. The reaction is carried out under or without a catalyst. The average molecular weight of the polysiloxane used here is 200-20000
and preferably 300 to 18,000. The appropriate proportion of the polysiloxane used is 0.95 to 1.05 mol based on the total amount of diisocyanate polyamide urethane.

Reaction solvents include polar solvents as well as aliphatic or aromatic halogenated solvents, such as N,N-dimethylamide, N,N-dimethylformamide,
Hexamethylphosphortriamide, m-cresol, o-dichlorobenzene, chlorobenzene, phenol, etc. can be used.

The amount of solvent used can vary within a wide range and is generally from 50% (wt%) to 95%, preferably from 60 to 80%, based on the total amount of reactants.

The polycondensation reaction to obtain the block copolymer can be carried out simply by heating the reaction mixture at a temperature in the range of 110 to 180°C, preferably 120 to 160°C. When adding the reaction components, each reaction component is added dropwise little by little, and after the reaction is completed, the copolymer is separated from the reaction solvent and purified by a known method to obtain it.

The production reaction according to the invention can advantageously be carried out in two stages. That is, in the first step, either the dicarboxylic acid polyamide at both ends or the diamine polyamide at both ends is reacted with a part or the entire amount of the diisocyanate compound in a solvent, and then in the second step, the diol at both ends and the dicarboxylic acid polyamide at both ends are reacted. A polyamide/polysiloxane block copolymer is produced by introducing a selected one of an acid and a polysiloxane having diamines at both ends into the same solvent.

Due to its excellent physical properties, the block copolymer of the present invention is suitable for use in the production of sealing materials such as hoses, tubes, seals, and packing, or belts such as caterpillars and belts.

EXAMPLES The present invention will be described below with reference to Examples, but the present invention is not limited to these Examples.

Example 1 A cooling tube, a dropping funnel, a stirrer, and a nitrogen introduction tube were attached to a four-necked flask, and 50 ml of chlorobenzene and 50 ml of phenol were put into the reactor, and while bubbling _N2 , a double-terminated diamine lauryl lactam oligomer ( Number average molecular weight = 2300) 25g
(10.6 mmol) was added, heated to 110°C, and then slowly cooled to around room temperature. 5.5 g (21.7 mmol) of dodecamethylene diisocyanate was gradually added using a dropping funnel with vigorous stirring. After the dropwise addition was completed in about 5 minutes, stirring was continued for about 30 minutes. Next, both terminal diol polydimethylsiloxane (=
1700) 18.5g (10.6mmol) was added to 0.1ml of a 4% by weight solution of DBU (diazabicycloundecene) in N,N-dimethylacetamide, and 20ml of chlorobenzene was added.
The solution was diluted with water and gradually added dropwise over about 30 minutes at room temperature while stirring using a dropping funnel. Further, after the dropwise addition was completed, the mixture was heated under reflux at 130°C for 1 hour. This reaction mixture was precipitated in methanol, finely ground in methanol using a grinder, and then vacuum dried (0.1 mmHg) at 80°C for about 3 hours.

After rectifying the solvent, zeolite A-3 8~
12 mesh (manufactured by Wako Pure Chemical Industries, Ltd.) was added and a sufficiently dried solvent was used.

A 2 mm thick plate obtained by compression molding the obtained polymer powder sample exhibited the following physical properties. Glass transition temperature [Tg (℃)] 163, recrystallization temperature [Tc
(℃)〕98 (Measurement was carried out using a differential thermal analyzer.) Tensile strength at 20℃: 438Kg/cm ² (JIS K-
7113) Elongation at break at 20℃: 183% (JIS K
-7113) Example 2 Using the same apparatus as in Example 1, put 100 ml of chlorobenzene and 50 ml of phenol into the reactor, and while bubbling _N2 , 25 g of double-terminated diamine lauryl lactam oligomer (=2300) was added.
(10.6 mmol) was added, heated to 130°C, and then gradually cooled to around room temperature. 5.48 g (21.7 mmol) of dodecamethylene diisocyanate was gradually added into the reactor using a dropping funnel while stirring vigorously. After the dropwise addition is completed in about 5 minutes, stirring is continued for about 30 minutes. Next, 26.0 g (10.9 mmol) of both-end carbinol polydimethylsiloxane (=2400) was diluted with 50 ml of chlorobenzene and gradually added dropwise over 1 hour without a catalyst. Further, after the dropwise addition was completed, the mixture was heated under reflux at 130° C. for 1 hour. This reaction mixture was precipitated in methanol, pulverized in methanol, and then dried in a vacuum dryer (0.1 mmHg) at 80° C. for about 3 hours.

A plate with a thickness of 2 mm obtained by compression molding the obtained powder sample exhibited the following physical properties.

Tg (℃): 165 Tc (℃): 105 Tensile strength at 20℃: 522Kg/cm ² Elongation at break at 20℃: 300%

Claims (1)

[Scope of Claims] 1. A product obtained by polycondensation of a lactam or α,ω-amino acid having a hydrocarbon chain of 2 to 15 carbon atoms, or a dicarboxylic acid and a diamine having a hydrocarbon chain of 2 to 15 carbon atoms. and a double-terminated dicarboxylic acid polyamide or a double-terminated diamine polyamide with a number average molecular weight of 500 to 10,000 and having a carboxyl group or an amino group at both ends and represented by the following general formula (1), (2) or (3). One or more polysiloxanes selected from polysiloxanes having a number average molecular weight of 200 to 20,000 and having hydroxyl groups, amino groups, or carboxyl groups at both ends are bonded by a compound having two isocyanate groups. Polyamide characterized by
A method for producing a polysiloxane block copolymer. (M is alkylene group, phenylene group or oxyethylene group, R is H, CH ₃ or phenyl group, n is 0
~50, t is 0 to 5) (M and R are the same as formula (1), n is 0 to 50, p is 0 to
5) (M and R are the same as formula (1), n is 0 to 50, q is 0 to
5)