JPH0251926B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel copolyamide resin. Polyamide resins are used in a wide range of applications including fibers, but a major drawback when used primarily as molded products is that their dimensions and physical properties change greatly depending on moisture. As a result of intensive exploration and research in order to obtain a polyamide resin that is less affected by moisture, that is, has a lower water absorption rate, the present inventor has found that polybutadiene or butadiene copolymer having carboxylic acid groups or amino groups at both ends has already been found.
It was discovered that the copolymer copolymerized with commonly used polyamide resin monomers, and furthermore, the copolymer was found to have a low water absorption rate (Japanese Patent Application No. 123135/1982). However, this copolyamide is relatively easily altered by heat, and therefore has two drawbacks. One is that special considerations such as lowering the temperature are required to avoid deterioration during polymerization, and the other is that it becomes brittle in a short period of time when used in a high temperature atmosphere. An object of the present invention is to provide a new copolyamide that is less affected by moisture and has improved thermal stability. The inventor of the present invention believes that the cause of poor thermal stability of polyamide copolymerized with polybutadiene or butadiene copolymer is the double bond, and as a result of extensive studies, it has been found that both terminals have a carboxylic acid group or an amino group. They discovered that polybutadiene with hydrogenated double bonds copolymerized with commonly used polyamide resin monomers, and further discovered that the copolymer had low water absorption and good thermal stability. This has led to the present invention. That is, the present invention uses 99 to 5 parts by weight of a polyamide polymer component having one or more types of repeating units represented by the following general formula (1) or (2) and an average molecular weight of 500 to 10,000, which has carboxylic acid groups or amino groups at both ends. The object of the present invention is to provide a new copolymerized polyamide resin having a low water absorption rate and good thermal stability, which is obtained by copolymerizing 1 to 95 parts by weight of a polybutadiene component whose double bonds are hydrogenated. -NH( _CH2 ) _o CO- (1) (In the formula, n is an integer from 5 to 11) -NHXNHCOYCO- (2) (In the formula, X is C _n H _2n (m is an integer from 6 to 12), The copolyamide of _the present invention _has a low water absorption rate,
It is suitable for use in molded products made by injection, extrusion, etc. because it has little change in dimensions and physical properties due to moisture and has good thermal stability. This copolymer can also be used as a thermal adhesive with low water absorption. Furthermore, copolymers containing 30% by weight or more of polybutadiene with hydrogenated double bonds are flexible and have excellent impact resistance, so they can be used in applications that require flexibility or as impact modifiers. It can be advantageously used as Examples of monomers constituting the polyamide polymer component of the copolyamide of the present invention include caprolactam, lauryllactam, 11-aminoundecanoic acid, 12-aminododecanoic acid, hexamethylene adipamide, hexamethylene sepacimide, hexamethylene In addition to methylenedodecamide, diamine salts of ring-containing dibasic acids such as terephthalic acid and cyclohexanedicarboxylic acid, dibasic acid salts of diamines such as phenylenediamine, cyclohexanediamine, and isophoronediamine, and the like. Polybutadiene in which a double bond having a carboxylic acid group or an amino group at both ends is hydrogenated is produced by hydrogenating polybutadiene having a carboxylic acid group or an amino group at both ends. Polybutadiene to be hydrogenated includes 1,2 bonds, 1,4 trans bonds, 1,4
It may contain any bond such as a cis bond, but
From the viewpoint of ease of hydrogenation, it is desirable to have a high proportion of 1,2 bonds. It is technically difficult to perform complete hydrogenation, so polybutadiene with a hydrogenation rate of 70% or more is preferably used;
% or more of polybutadiene is more preferably used. It is technically difficult to carry out 100% carboxylation or amination of both ends of polybutadiene.
Therefore, the ends of hydrogenated polybutadiene are also 100%
It is unlikely to become a carboxylic acid group or an amino group. Hydrogenated polybutadiene with a carboxylic acid terminal ratio or amino terminal ratio of 60% or more is preferably used, and the same terminal ratio is 75%.
% or more of hydrogenated polybutadiene is more preferably used. If the molecular weight of the hydrogenated polybutadiene is less than 500, the effect of reducing water absorption will be small, and if it is greater than 10,000, it will be difficult to obtain desirable physical properties. In the copolymerized polyamide resin of the present invention, when the polyamide polymer component exceeds 99 parts by weight, each property becomes almost the same as that of hydrogenated polyamide not containing polybutadiene, and when the hydrogenated polybutadiene component exceeds 95 parts by weight. Both are unfavorable because the properties are almost the same as those of hydrogenated polybutadiene. The copolymerization method for obtaining the copolyamide resin of the present invention may be either condensation polymerization or ring-opening polymerization. In addition, in order to adjust the molecular weight of the copolymer, a diamine or a dicarboxylic acid can be added in consideration of the number of moles of hydrogenated polybutadiene. Examples of diamines that can be used include alkylene diamines such as hexamethylene diamine and dodecamethylene diamine, alicyclic diamines such as cyclohexane diamine, aromatic diamines such as phenylene diamine, and isophorone diamine. Dicarboxylic acids include aliphatic dicarboxylic acids such as adipic acid, sebacic acid, and dodecanedioic acid;
Alicyclic carboxylic acids, aromatic dicarboxylic acids such as phthalic acid may be used. Next, the present invention will be explained with reference to examples. Example 1 76.40 g of 12-aminododecanoic acid, 1.57 g of hexamethylene diamine, polybutadiene with hydrogenated carboxylic acid at both ends (98% hydrogenation of polybutadiene with 80% or more of 1,2 vinyl bonds, terminal carboxylic acid group concentration)
0.935meg/g) 28.92g was placed in a 500ml Erlenmeyer flask, and the flask was flushed with nitrogen.
Heated to 250°C. As 12-aminododecanoic acid melts, condensation begins and water comes out in the form of bubbles.
After heating at 250°C for 3 hours, the mixture was cooled, the Erlenmeyer flask was broken, and the polymer was taken out. A light yellow, translucent, impact-resistant polymer was obtained. This polymer has a ratio of nylon 12 component/hydrogenated polybutadiene-hexamethylene diamine condensate component of 70/30. This polymer was dissolved in metacresol and 0.5%
The relative viscosity of the solution was measured at 25°C using an Ostwald viscometer and found to be 1.43. This polymer was pressed into a flat plate and immersed in water at 40°C for 10 days.The water absorption was measured using a DuPont moisture meter and found to be 1.21%. Additionally, DSC (Differential Scanning Calori−
The melting point was 172°C as determined by METAR). When nylon 12 homopolymer was measured in the same manner, it had a water absorption rate of 1.6% and a melting point of 178°C. Example 2 49.11 g of 12-aminododecanoic acid, 0.26 g of hexamethylene diamine, and 4.82 g of the hydrogenated polybutadiene used in Example 1 were placed in a 300 ml Erlenmeyer flask, and polymerization was carried out in the same manner as in Example 1. After cooling, the polymerized product was I took it out. A light yellow, translucent, hard and impact resistant polymer was obtained. This polymer consists of 12 nylon components/
The ratio of hydrogenated polybutadiene-hexamethylene diamine condensate components corresponds to 90/10. This polymer was measured in the same manner as in Example 1 and found to have a relative viscosity of 1.70, a water absorption rate of 1.49%, and a melting point of 176°C. Example 3 54.57 g of 12-aminododecanoic acid, 2.61 g of hexamethylene diamine, and 48.20 g of the hydrogenated polybutadiene used in Example 1 were charged into a separable flask (500 ml), nitrogen was flushed, and the flask was heated at 220° C. for 2 hours with stirring. A pale yellow, almost transparent, flexible polymer was obtained. This polymer has a ratio of nylon 12 component/hydrogenated polybutadiene-hexamethylene diamine condensate component of 50/50. This polymer was measured in the same manner as in Example 1 and found to have a relative viscosity of 1.30, a water absorption rate of 1.07, and a melting point of 167°C. Example 4 32.74 g of 12-aminododecanoic acid, 3.66 g of hexamethylene diamine, and 67.48 g of the hydrogenated polybutadiene used in Example 1 were charged into a 500 ml separable flask.
Polymerization was carried out in the same manner as in Example 3. A pale yellow and extremely flexible polymer was obtained. This polymer has a ratio of nylon 12 component/hydrogenated polybutadiene-hexamethylene diamine condensate component of 30/70. This polymer was measured in the same manner as in Example 1 and found to have a relative viscosity of 1.18, a water absorption rate of 0.95, and a melting point of 155°C. Example 5 ε-caprolactam 81g, ε-aminocaproic acid
10.43g of hexamethylene diamine, 0.52g of hexamethylene diamine, and 9.64g of the hydrogenated polybutadiene used in Example 1 were placed in a 500ml flask, and heated to 180°C under nitrogen flow and stirring.
Heat for 30 minutes, raise the temperature to 250℃ over 1 hour,
Heating was continued for 4 hours at °C. A pale yellow, translucent polymer was obtained. After crushing this polymer in liquid nitrogen, it was washed with 60℃ hot water.
When extracted for 24 hours, the extraction loss was about 5%.
Since the extract is estimated to be mostly caprolactam, this polymer is a copolymer with a ratio of nylon 6 component/hydrogenated polybutadiene-hexamethylene diamine condensate component of approximately 85/10. The extracted copolymer could be molded into a strong sheet by press molding. When this copolymer is dissolved in metacresol,
A homogeneous solution was obtained. The relative viscosity of the 0.5% metacresol solution at 25°C was 1.62. The melting point of this copolymer measured by DSC was 214°C. On the other hand, polymerization was carried out in the same manner as in this example except for hydrogenated polybutadiene and hexamethylene diamine,
The water-extracted polymer nylon 6 homopolymer had a melting point of 216°C. Elemental analysis of the copolymer and nylon 6 homopolymer yielded the results shown in Table 1.

[Table] Example 6 Dodecanedioic acid/hexamethylene diamine salt
89.29 g, hexamethylene diamine 1.03 g, and 19.29 g of the hydrogenated polybutadiene used in Example 1 were charged into a 500 ml flask, and while nitrogen was flushed and stirred, 200 g of hexamethylene diamine was added.
It was heated at ℃ for 30 minutes to melt the contents, and the temperature was gradually raised to 240℃ over 30 minutes. After heating at 240°C for 2 hours, the mixture was further heated at 260°C for 2 hours to obtain a pale yellow translucent polymer. This polymer is a copolymer having a ratio of nylon 612 component/hydrogenated polybutadiene-hexamethylene diamine condensate component of 80/20. This polymer could be formed into a strong sheet by press molding. When this copolymer is dissolved in metacresol,
A homogeneous solution was obtained. The relative viscosity of the 0.5% metacresol solution at 25°C was 1.63. The melting point of this copolymer measured by DSC was 212°C. On the other hand, the melting point of the polymer nylon 612 homopolymer polymerized in the same manner as in this example except for hydrogenated polybutadiene and hexamethylene diamine was 217°C.
It was hot. Elemental analysis of the copolymer and nylon 612 homopolymer yielded the results shown in Table 2.

【table】

Claims (1)

[Claims] 1 Polyamide polymer component 99-5 having one or more repeating units represented by the following general formula (1) or (2)
A new copolymerized polyamide resin obtained by copolymerizing 1 to 95 parts by weight of a polybutadiene component hydrogenated by 70% or more to a double bond having an average molecular weight of 500 to 10,000 and having carboxylic acid groups or amino groups at both ends. . -NH( _CH2 ) _o CO- (1) (In the formula, n is an integer from 5 to 11) -NHXNHCOYCO- (2) (In the formula, X is C _n H _2n (m is an integer from 6 to 12), represents an isophorone group, a phenylene group or a cyclohexylene group, Y represents C _l H _2l (l is an integer from 4 to 10), a phenylene group or a cyclohexylene group)