JPH0211628B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a polyamide resin composition containing a novel low water absorption copolymerized polyamide resin. [Prior art and problems to be solved by the invention] As is well known, polyamide resin is used in a wide range of applications including fibers, but due to its structure with amide bonds, it inherently has a high water absorption rate, and the dimensions of molded products are limited. It has drawbacks such as poor stability and physical properties such as electrical characteristics that change significantly depending on humidity. For example, polyamide resin has temperature dependence of its impedance and has a clear melting point because it is a crystalline polymer, and it can be used as a temperature fuse to create heat-sensitive elements in heating elements such as electric blankets and electric carpets. However, in such applications, it is necessary that the impedance of the polyamide resin is not affected by humidity. Therefore, among the polyamide resins, Comparative Example Nylon 11 and Nylon 12, which have low hygroscopicity, are used for such applications, but even so, sufficiently satisfactory performance is not obtained in terms of being affected by humidity. The purpose of the present invention is to improve water absorption, which is an inherent drawback of polyamide resin, and to create a polyamide blended with an improved new copolyamide resin that has mechanical properties, moldability, and flexibility specific to polyamide resin. An object of the present invention is to provide a resin composition. [Means for Solving the Problems] That is, the present invention comprises 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 carbon atoms at both ends. The present invention relates to a polyamide resin composition containing a novel copolyamide resin obtained by copolymerizing 1 to 95 parts by weight of a polyolefin component having an average molecular weight of 500 to 10,000, which is an acid group, an amino group, or a hydroxyl group. -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, and Y represents C _l H _2l (l is an integer of 4 to 10), a phenylene group or a cyclohexylene group) The above general formula constituting the copolymerized polyamide of the present invention Examples of monomers constituting the polyamide polymer component having one or more repeating units represented by (1) or (2) include caprolactam, lauryllactam, and 11-aminoundecane, which correspond to formula (1). The salts of hexamethylene diamine and adipic acid, the salts of hexamethylene diamine and sebacic acid, and the salts of hexamethylene diamine and dodecanedioic acid correspond to formula (2). In addition to salts, examples include diamine salts of ring-containing dibasic acids such as terephthalic acid and cyclohexane dicarboxylic acid, and dibasic acid salts of diamines such as phenylene diamine, cyclohexane diamine, and isophorone diamine. Further, the polyolefin component constituting the copolyamide of the present invention has carboxylic acid groups at both ends,
A polyolefin having an amino group or a hydroxyl group is obtained, for example, by radical polymerization from one or more olefin monomers, but in order to introduce a carboxylic acid group, an amino group, or a hydroxyl group functional group to both ends, an initiator, In addition to the solvent, polymerization conditions such as temperature and pressure are appropriately selected. Alternatively, the polyolefin component of the present invention can be obtained by linearly polymerizing a monomer having two or more double bonds by introducing a functional group selected from a carboxylic acid group, an amino group, or a hydroxyl group at the terminal thereof. It can also be obtained by hydrogenating . For example, by subjecting polybutadiene to living polymerization, terminating the polymerization with an epoxy compound to introduce hydroxyl groups at the ends, and further hydrogenating this, a polyolefin having hydroxyl groups at both ends can be obtained. The polybutadiene to be hydrogenated has a 1,2-bond,
It may contain any bond such as a 1,4-trans bond or a 1,4-cis bond. However, from the viewpoint of ease of hydrogenation, it is desirable to have a high proportion of 1,2-bonds. There is no functional group mentioned above except at both ends of the polyolefin, that is, in the middle of the main chain, and 100% of the functional groups at both ends are present.
Ideally, it would be possible to obtain a product with functional groups introduced, but it is unavoidable that some functional groups will be introduced in the middle of the main chain due to chain transfer, especially during radical polymerization, and especially during living polymerization termination. sometimes 100%
It is also difficult to introduce functional groups at both ends. Therefore, as the polyolefin component for producing the copolyamide of the present invention, a polyolefin in which 1.2 to 3.0 of the above functional groups are introduced per molecule can be used, and the number of functional groups per molecule is
Polyolefins having a molecular weight of 1.5 to 2.2 may be more preferably used. In addition, it is technically difficult to completely hydrogenate a polymer of monomers having two or more double bonds. A hydrogenated polymer with a hydrogenation rate of 90% or more is preferably used, and a hydrogenated polymer with a hydrogenation rate of 90% or more is more preferably used. Hydrogenation rate
Hydrogenated polymers that are not 100% may not be included in polyolefins in the strict sense of the structure, but
The polyolefin component referred to in the present invention also includes polymers with a hydrogenation rate of less than 100%. In addition, in the polyolefin component of the present invention, if the molecular weight is less than 500, there is little effect of reducing water absorption, and if it is greater than 10,000, it is difficult to obtain favorable physical properties, so the average molecular weight is 500 to 500.
Preferably 10000. Regarding the copolymerization ratio of both components 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 polyamide containing no polyolefin component, and when the polyolefin component exceeds 95 parts by weight, If it exceeds it, the properties will be almost the same as that of polyolefin, so neither is preferable. The copolymerization ratio is preferably 5 to 70 parts by weight of the polyolefin component to 95 to 30 parts by weight of the polyamide polymer component. In the polymerization method for obtaining the copolyamide resin of the present invention, when the functional group of the polyolefin used is a carboxylic acid group or an amino group,
It is polymerized by essentially the same method as for obtaining known polyamides. Most easily, the monomers for the polyamide polymer component and The copolyamide of the present invention can be obtained by copolymerizing with a polyolefin containing a carboxylic acid group or an amino group. At this time, in order to adjust the molecular weight of the copolymer, a diamine or a dicarboxylic acid may be added, taking into consideration the number of moles of the polyolefin component. 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 dicarboxylic acids, aromatic dicarboxylic acids such as phthalic acid can be used. On the other hand, when the functional group of the polyolefin used is a hydroxyl group, the copolymerization method for obtaining the copolyamide resin of the present invention may be either condensation polymerization or ring-opening polymerization. In this case, in order to adjust the molecular weight of the copolymer, dicarboxylic acid can be added in consideration of the number of moles of the polyolefin component. As the dicarboxylic acid, aliphatic dicarboxylic acids such as adipic acid, sebacic acid, and dodecanedioic acid, alicyclic dicarboxylic acids, and aromatic dicarboxylic acids such as phthalic acid can be used. In order to synthesize the copolyamide resin according to the present invention using such a polyolefin having hydroxyl groups at both ends, a condensation reaction of a dicarboxylic acid and an amino acid or a dicarboxylic acid and a diamine, or ring-opening of a lactam in the presence of a dicarboxylic acid is performed. By polymerization,
A polyamide oligomer having a terminal carboxylic acid group is formed, and a block copolymer is formed by an ester formation reaction between the terminal carboxylic acid group of this oligomer and a polyolefin having a hydroxyl group at both ends. The polyolefin diol may be added after the synthesis of the polyamide oligomer, or it may be allowed to coexist from the beginning of the polyamide synthesis so that the amide bond-forming reaction and the ester bond-forming reaction occur in parallel. In any case, since there is a difference in the equilibrium constants of the reversible reactions between the amide bond formation reaction and the ester bond formation reaction, the amide bond formation occurs first, and the block copolymer is completed by the ester bond formation reaction. For this purpose, a desorbed water removal process under high temperature and reduced pressure is essential. In addition, a polyester oligomer having a carboxylic acid group at the end is synthesized by first carrying out a condensation reaction between a polyolefin diol and a dicarboxylic acid,
A method in which a polycondensation reaction of an amino acid or a dicarboxylic acid and a diamine or a ring-opening polymerization of a lactam is performed in the presence of this oligomer to obtain a block copolymer through a condensation reaction accompanied by a transesterification reaction, or a method in which a block copolymer is obtained by a condensation reaction accompanied by a transesterification reaction, or the above-mentioned polyester oligomer and polyamide oligomer It is also possible to obtain a block copolymer by a condensation reaction accompanied by a transesterification reaction. A titanium-based catalyst gives good results in the production of the copolyamide resin of the present invention. Particularly preferred are tetraalkyl titanates such as tetrabutyl titanate and tetramethyl titanate, and metal salts of titanium oxalate such as potassium titanium oxalate. Other catalysts include tin compounds such as dibutyltin oxide and dibutyltin laurate, and lead compounds such as lead acetate. In a small amount of copolymerization, other diol components such as cyclohexanedimethanol and 1,6-hexanediol and polyfunctional compounds such as trimesic acid, glycerin and pentaerythritol may be contained. The copolyamide resin of the present invention is a block polymer consisting of a polyamide polymer component and a polyolefin component, and the molecular weight of the copolyamide resin of the present invention is approximately 5000 to 5000 as a number average molecular weight.
The range is 500000. The copolyamide resin of the present invention contains antioxidants, thermal decomposition stabilizers, etc. during polymerization or after polymerization and before molding.
Stabilizers such as light resistance agents, hydrolysis resistance improvers, colorants, flame retardants, reinforcing agents, fillers, various molding aids,
Additives such as plasticizers may be optionally mixed and used. The polyamide resin composition of the present invention is made of nylon.
It is obtained by blending the copolyamide resin of the present invention with a polyamide resin selected from 6, 66, 11, 12 and 612. The blending amount is 0.1 to 70 parts by weight of the copolyamide resin of the present invention to 99.9 to 30 parts by weight of the above polyamide resin. [Effect of the invention] The copolyamide of the present invention has a low water absorption rate,
Since there is little change in dimensions and physical properties due to moisture and good thermal stability, the polyamide resin composition of the present invention containing the same is suitably used for molded products by injection, extrusion, etc. It can also be used as a thermal adhesive, solution adhesive, or coating agent with low water absorption. Furthermore, a copolymer containing 30% by weight or more of the polyolefin component is flexible and has excellent impact resistance, so the polyamide resin composition of the present invention has significantly improved impact resistance. . Furthermore, since the copolymerized polyamide of the present invention has low water absorption, the humidity dependence of electrical properties, especially impedance, is small, and the polyamide block has properties as a thermal fuse due to its distinct melting point, so it was blended. The polyamide resin composition of the present invention can be particularly advantageously used as a heat-sensitive element for electric blankets, electric carpets, etc., which utilizes the temperature dependence of impedance and thermal fusibility. [Example] Next, the present invention will be described with reference to an example. Example 1 In a 40 autoclave, lauryl lactam 1.4
Kg, polybutadiene with hydrogenated carboxylic acid at both ends (polybutadiene with 80% or more of 1,2 vinyl bonds)
98% hydrogenation, terminal carboxylic acid group concentration 0.935meq/g)
578g, hexamethylene diamine 31.4g, water 700g
After charging and purging with nitrogen, the temperature inside the can was raised to 270°C over 3 hours. The pressure inside the can is 20
The pressure was adjusted to release to Kg/cm ² . 270℃,
After continuing the reaction for 5 hours under the condition of 20 Kg/cm ² , the pressure was gradually released over a period of 4 hours to bring the pressure to 0, and the temperature was gradually lowered to 250°C. At the same time as the pressure release was completed, nitrogen was flowed into the can and two hours later, the polymer was extruded from the bottom of the autoclave and pelletized. This polymer has a ratio of nylon 12/hydrogenated polybutadiene-hexamethylene diamine condensate components.
Equivalent to 70/30. The relative viscosity of this polymer was 1.57. Nylon 12 homopolymer having a relative viscosity of 1.90 and this copolymer were mixed at weight ratios of 70/30 and 50/50, kneaded and extruded using a 30 mmφ extruder, and pelletized to obtain a blended product. A blend of these two types of copolymers and a nylon 12 homopolymer with a relative viscosity of 1.90 were molded into a notched Shapey impact test piece.
Charpy impact strength was measured at 23°C and 0°C. The results are shown in Table-1. Table 1 shows that this copolymer not only has excellent impact resistance, but also that blending this copolymer improves the impact strength of nylon 12 homopolymer. 【table】

Claims (1)

[Scope of Claims] 1 (a) 99.9 to 30 parts by weight of a polyamide resin selected from nylon 6, 66, 11, 12 and 612; (b) represented by the following general formula (1) or (2); 99 to 5 parts by weight of a polyamide polymer component having one or more types of repeating units; and 1 to 95 parts by weight of a polyolefin component having an average molecular weight of 500 to 10,000 and having carboxylic acid groups, amino groups, or hydroxyl groups at both ends.
Copolymerized polyamide resin obtained by copolymerizing parts by weight
A polyamide resin composition comprising 0.1 to 70 parts by weight. -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, and Y represents C _l H _2l (l is an integer of 4 to 10), a phenylene group, or a cyclohexylene group) 2 The ratio of the polyamide polymer component to the polyolefin component is The polyamide resin composition according to claim 1, wherein the polyolefin component is 5 to 70 parts by weight relative to 95 to 30 parts by weight of the polymer component.