Aliphatic long-carbon-chain copolyamide resin containing oxamide component and preparation method of aliphatic long-carbon-chain copolyamide resin

Abstract

The invention discloses aliphatic long-carbon-chain copolyamide resin containing an oxalyl amide component, raw materials comprise long-carbon-chain diamine, oxalyl diamine and long-carbon-chain dicarboxylic acid, the molar ratio of the long-carbon-chain diamine to the oxalyl diamine is (30-80): (70-20), and the ratio of the total mole number of the long-carbon-chain diamine and the oxalyl diamine to the mole number of the long-carbon-chain dicarboxylic acid component is 1: 1; the long carbon chain diamine is at least one of straight chain diamines with the carbon atom number of 10-12; the oxalyl diamine is at least one of diamines containing an oxalyl structure; and the long-carbon-chain dicarboxylic acid is one or two of straight-chain dicarboxylic acids with the carbon atom number of 10-14. The aliphatic long-carbon-chain copolyamide resin disclosed by the invention has excellent yield strength and heat resistance, and the low water absorption rate of the long-carbon-chain copolyamide resin is retained; the mechanical strength and the heat resistance are equivalent to those of the PA6 resin, the stretchability is better, and the water absorption is lower.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer material preparation, and in particular relates to an aliphatic long carbon chain copolyamide resin containing an oxalamide component, a preparation method thereof and a molded product thereof. Background Art

[0002] Long-chain polyamide generally refers to polyamide in which the number of carbon atoms between two adjacent amide groups in the molecular chain is not less than 10. In addition to most of the characteristics of general polyamides, such as solvent resistance and easy processing, this type of polyamide also has unique advantages such as low water absorption, excellent dimensional stability and dielectric properties, high flexibility and fatigue resistance. The density of polar amide groups in long-chain polyamide molecules is relatively low. Although it avoids the problem of high water absorption caused by high-density amide groups in short-chain polyamides such as PA6, the reduction in amide group concentration will lead to low water absorption, and will also weaken the interaction between molecular chains, which will weaken the mechanical strength and heat resistance of long-chain polyamide resins.

[0003] For example, patent document CN1493602A discloses a long carbon chain aliphatic nylon, and the tensile yield strength of the prepared nylon 1212, nylon 1313, nylon 1414 and nylon 1013 are only 32.8, 23.1, 31.4 and 29.2 MPa respectively, the tensile breaking strength is only 43.8, 48.2, 46.6 and 46.3 MPa respectively, and the water absorption rate is 0.4%, 0.3%, 0.2% and 0.3% respectively. Except for a few aliphatic long carbon chain polyamide resins such as PA1010, the tensile strength of most aliphatic long carbon chain polyamide resins can reach about 60 MPa, and the tensile strength of most aliphatic long carbon chain polyamide resins is less than 50 MPa. Therefore, the mechanical strength of common aliphatic long carbon chain polyamide resins such as PA1010, PA1012 and PA1212 is usually much lower than that of short chain polyamides such as PA6, which is not conducive to the application and promotion of aliphatic long carbon chain polyamide resins in more fields.

[0004] Copolymerization synthesis is an effective means of modifying polyamide resins. Patent document CN1288905A discloses a long carbon chain copolyamide and a preparation method thereof, which is obtained by copolymerizing decanediamine, lauryl diamine and sebacic acid or lauric acid to obtain an aliphatic long carbon chain copolyamide with more outstanding electrical properties, water absorption and toughness, but its heat resistance and mechanical strength are damaged. Patent CN1214349A discloses an aliphatic long carbon chain copolyamide and a preparation method thereof, which exhibits better low-temperature resilience and flexibility, but its heat resistance and mechanical strength are severely damaged. Patent CN1746208A publicly reports a block copolyamide and a preparation method thereof, including copolymerizing a long carbon chain polyamide with a short-chain aliphatic polyamide such as PA6 to obtain an aliphatic copolyamide with better low-temperature resilience and flexibility, but its mechanical properties are poor, and its mechanical strength is much lower than that of short-chain polyamides such as PA6.

[0005] Patent document CN118725288A discloses a copolyamide material and a preparation method thereof, which uses polyamide 66 salt and long carbon chain amide salt as raw materials, introduces a long carbon chain structure into polyamide 66, reduces the proportion of amide groups in the copolymer, and reduces the hygroscopicity of the copolyamide compared with polyamide 66. It has good dimensional stability in a humid environment, improves the toughness and softness of the product, and has excellent tensile strength or substantially no degradation. However, there is a contradictory relationship between the mechanical strength and dimensional stability in the document, and the mechanical properties of the copolyamide material with high dimensional stability are poor. Summary of the invention

[0006] The purpose of the present invention is to provide an aliphatic long carbon chain copolyamide resin containing an oxamide component obtained by copolymerizing a conventional aliphatic long carbon chain polyamide and an oxamide component, and a preparation method and a molded product thereof, in view of the problems existing in the prior art. The polyamide resin has equivalent or better mechanical strength than pure PA6 resin, while retaining the low water absorption and high flexibility inherent in the long carbon chain polyamide resin, and has better heat resistance than the existing aliphatic long carbon chain polyamide resin.

[0007] The aliphatic long carbon chain copolyamide resin containing oxalamide components of the present invention comprises raw materials including long carbon chain diamine, oxalyl diamine and long carbon chain dicarboxylic acid, wherein the molar ratio of the long carbon chain diamine to the oxalyl diamine is (30-80):(70-20), and the ratio of the total molar number of the long carbon chain diamine and the oxalyl diamine to the molar number of the long carbon chain dicarboxylic acid component is 1:1;

[0008] The long carbon chain diamine is at least one of the straight chain diamines with carbon atoms of 10 to 12; the oxalyl diamine is at least one of the diamines containing the oxamide structure [-HN-(C=O)-(C=O)-NH-], preferably at least one of oxalyl dibutylene diamine, oxalyl dipentane diamine, oxalyl dihexane diamine, oxalyl dioctane diamine, oxalyl didecane diamine or oxalyl dicyclohexane diamine; the long carbon chain dicarboxylic acid is one or two of the straight chain dicarboxylic acids with carbon atoms of 10 to 14.

[0009] The relative viscosity η of the aliphatic long carbon chain copolyamide resin containing oxalamide component at 25°C is r The molecular weight of the alloy is 1.8-5.0 (96% concentrated sulfuric acid, 1.0 g / dl), the yield strength is 70.4-85.0 MPa, the elongation at break is 140%-400%, the water absorption is 0.1%-0.7%, and the heat deformation temperatures under loads of 1.80 MPa and 0.45 MPa bending stress are 58.0-71.5°C and 164.5-174.0°C, respectively.

[0010] The method for preparing the aliphatic long carbon chain copolyamide resin containing oxalamide components of the present invention comprises subjecting a mixture of a long carbon chain diamine, oxalyl diamine and a long carbon chain dicarboxylic acid to a polycondensation reaction in a segmented or continuous manner, including a pre-polymerization step and a post-polymerization step;

[0011] The prepolymerization process comprises the following steps: adding a mixture of a long carbon chain diamine, oxalyl diamine and a long carbon chain dicarboxylic acid into a reactor, adding an amidation catalyst, heating and stirring at normal pressure under nitrogen protection, and reacting for 2 to 5 hours at a temperature of 110 to 170° C.;

[0012] The post-polymerization process comprises the following steps: under nitrogen protection and normal pressure conditions, heating the product of the previous polycondensation process to a set temperature in a reactor for continuous reaction, and cooling to room temperature after the reaction to obtain a polyamide resin; the set temperature is 180 to 300° C., preferably 200 to 280° C., and more preferably 220 to 270° C.; the continuous reaction time is 1 to 12 hours, preferably 2 to 9 hours, and more preferably 3 to 6 hours.

[0013] The post-polymerization step may be carried out under reduced pressure as required, and the final pressure reached by the reduced pressure polymerization is 10 to 1000 Pa, preferably 30 to 100 Pa.

[0014] The oxalyl diamine is prepared according to the prior art (for example, the method disclosed in patent document CN112521303A), and the specific preparation method comprises the following steps: under nitrogen protection and stirring, an ethanol solution of diethyl oxalate is added dropwise to an ethanol solution of butanediamine, pentamethylenediamine, hexamethylenediamine, octanediamine, decanediamine or cyclohexamethylenediamine, and after the addition is completed, the temperature is raised and refluxed for reaction for 8 hours, and then the filter cake obtained by filtration is washed with ethanol and water in turn, and dried to obtain a white oxalyl diamine component; wherein the molar ratio of the diamine used to the oxalic acid diester is 3:1.

[0015] The amidation catalyst is a catalyst commonly used in polyamide reactions, and is usually at least one of potassium hypophosphite, sodium hypophosphite, magnesium hypophosphite, calcium hypophosphite, zinc hypophosphite, potassium phosphite, sodium phosphite, magnesium phosphite, calcium phosphite, zinc phosphite, potassium phosphate, magnesium phosphate, calcium phosphate, zinc phosphate, hypophosphorous acid, phosphorous acid, and phosphoric acid. Preferably, the addition amount of the amidation catalyst is 0.05-0.3% of the total mass of the mixture.

[0016] Without prejudice to the effects of the present invention, the aliphatic long carbon chain copolyamide resin containing oxamide components described in the present invention may also be added with auxiliary agents as needed during or after the polycondensation reaction, and the auxiliary agents include but are not limited to flame retardants, antistatic agents, antioxidants, light stabilizers, colorants, ultraviolet absorbers, antibacterial agents and / or crystallization promoters.

[0017] The molded product of the aliphatic long carbon chain copolyamide resin containing oxalamide components described in the present invention is manufactured by adopting a known molding and processing method suitable for polyamide, including but not limited to injection, extrusion, blow molding, hollow, hot pressing, casting or / and foaming, and processing it into any shape of sheet, film, fiber, wire, tube, regular or irregular block.

[0018] The molded products of the aliphatic long carbon chain copolyamide resin containing oxamide components described in the present invention can be used in a wide range of applications of aliphatic polyamide resins, such as automotive industry parts, electronic and electrical equipment, optical equipment parts, information and communication equipment, construction industry supplies, medical device industry parts, packaging materials and supplies, national defense and military equipment parts, medium transportation supplies, and household products.

[0019] Compared with the prior art, the present invention has the following advantages:

[0020] 1. The long-chain copolyamide resin of the present invention introduces an oxalamide structure that can form double high-density hydrogen bonds between molecular chains, which greatly improves the interaction between molecular chains and can promote the strength and modulus of the long-chain polyamide resin to be comparable to those of short-chain aliphatic nylons such as PA6, while retaining the low water absorption characteristics and high flexibility of the long-chain polyamide resin.

[0021] 2. The introduction of oxalamide structure in the long-chain polyamide resin of the present invention forms a hydrogen bond physical cross-linking network constructed by the double hydrogen bonds of oxalamide and the hydrogen bonds of conventional long-chain polyamide. The formed more stable physical cross-linking network requires a higher ambient temperature to be destroyed, thereby making it have better heat resistance than conventional long-chain polyamide resins.

[0022] 3. The oxalamide structure introduced into the long-chain polyamide resin of the present invention is derived from biomass resources, which effectively increases the bio-based content of the long-chain polyamide resin and is conducive to achieving the renewable and environmentally friendly polyamide resin. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is the H-NMR spectrum of the aliphatic long carbon chain copolyamide resin containing oxamide components prepared in Example 1 of the present invention.

[0024] Figure 2 This is an infrared spectrum of the aliphatic long carbon chain copolyamide resin containing oxamide components prepared in Example 1 of the present invention.

[0025] Figure 3 This is a differential scanning calorimetry test diagram of the aliphatic long carbon chain copolyamide resin containing oxalamide components prepared in Example 1 of the present invention.

[0026] Figure 4 This is a thermal stability test curve of the aliphatic long carbon chain copolyamide resin containing oxalamide components prepared in Example 1 of the present invention.

[0027] Figure 5 This is a stress-strain curve of the tensile test of the aliphatic long carbon chain copolyamide resin containing oxalamide components prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0028] The following examples are given to further illustrate the present invention. It is necessary to point out that the following are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited to the following examples. All technical solutions under the concept of the present invention belong to the protection scope of the present invention.

[0029] Example 1

[0030] The preparation method of aliphatic long carbon chain copolyamide resin containing oxalamide component comprises the following steps:

[0031] (1) Pre-condensation step: A mixture of 51.7 g (0.3 mol) of decanediamine, 279.1 g (0.7 mol) of oxalyldidecanediamine and 202.2 g (1 mol) of decanediic acid was added to a reaction vessel, and 0.54 g of sodium hypophosphite was added at the same time. After replacing with nitrogen, the temperature was raised under nitrogen protection and stirred at normal pressure to react. The temperature was controlled at 110° C. and the reaction was continued for 3 hours.

[0032] (2) Post-polycondensation step: To further increase the molecular weight, the product obtained in the pre-polycondensation step is first heated to 250°C in a reaction vessel under nitrogen and normal pressure, then decompressed to 80 Pa and reacted for 3 h. After the reaction, the product is cooled to room temperature to obtain a polyamide resin.

[0033] Figure 1 This is the H NMR spectrum of the aliphatic long carbon chain copolyamide resin containing oxamide components of Example 1, in which the proton peaks corresponding to the hydrogen on the amine group in the oxamide structure and the proton peak on the amine group in the conventional amide structure appear at 8.62ppm and 8.18ppm respectively, and the proton peaks of the hydrogen on the methylene adjacent to the amine group in the three types of amide bonds appear between 3.2-3.6ppm, indicating that the aliphatic long carbon chain copolyamide resin containing oxamide components has been prepared.

[0034] Figure 2 This is the infrared spectrum of the aliphatic long carbon chain copolyamide resin containing oxamide component of Example 1. -1 、1653cm -1 , and 1523cm -1 and 1511cm -1 The characteristic peaks corresponding to the NH group, amide I band and amide II band appeared at 1523 cm -1 and 1511cm -1 The two peaks indicate the co-existence of double hydrogen bonds of oxalamide and hydrogen bonds of conventional long carbon chain polyamides, and further indicate that an aliphatic long carbon chain copolyamide resin containing oxalamide components is prepared.

[0035] Figure 3 This is the differential scanning calorimetry test diagram of the aliphatic long carbon chain copolyamide resin containing oxalamide component of Example 1. It can be seen that the melting point of the aliphatic long carbon chain copolyamide resin containing oxalamide component is 217.8°C, and the processing temperature is lower than that of short-chain aliphatic polyamide resins such as PA6; at the same time, the aliphatic long carbon chain copolyamide resin containing oxalamide component shows an extremely sharp crystallization peak at 182.3°C, indicating that it has excellent crystallization properties.

[0036] Figure 4The thermal stability test curve of the aliphatic long carbon chain copolyamide resin containing oxalamide component in Example 1 shows that the initial thermal decomposition temperature (T 5％ ) can reach 403.2℃, indicating that it has excellent thermal stability.

[0037] Figure 5 The stress-strain curve of the tensile test of the aliphatic long carbon chain copolyamide resin containing oxalamide component of Example 1 shows that the material can be bent continuously within 6 mm, and its bending modulus can reach 1776 MPa, and the bending strength can reach 70.8 MPa, indicating that the material has good strength and modulus and relatively excellent load-bearing capacity.

[0038] Example 2

[0039] The preparation method of aliphatic long carbon chain copolyamide resin containing oxalamide component comprises the following steps:

[0040] (1) Pre-condensation step: A mixture of 103.4 g (0.6 mol) of decanediamine, 159.5 g (0.4 mol) of oxalyldidecanediamine and 202.2 g (1 mol) of decanediic acid was added to a reaction vessel, and 0.47 g of sodium hypophosphite was added at the same time. After replacing with nitrogen, the temperature was raised under nitrogen protection and stirred at normal pressure to react. The temperature was controlled at 120° C. and the reaction was continued for 3 hours.

[0041] (2) Post-polycondensation step: To further increase the molecular weight, the product obtained in the pre-polycondensation step was heated to 250°C in a reaction vessel under nitrogen protection and normal pressure, and the reaction was continued for 5 hours. After the reaction, the polyamide resin was obtained by cooling to room temperature.

[0042] Example 3

[0043] The preparation method of aliphatic long carbon chain copolyamide resin containing oxalamide component comprises the following steps:

[0044] (1) Pre-condensation step: A mixture of 120.6 g (0.7 mol) of decanediamine, 69.1 g (0.3 mol) of dibutylene oxalyl and 202.2 g (1 mol) of decanediic acid was added to a reaction vessel, and 0.59 g of hypophosphorous acid was added at the same time. After replacing with nitrogen, the temperature was raised under nitrogen protection and stirred at normal pressure to react. The temperature was controlled at 160°C and the reaction was continued for 4 hours.

[0045] (2) Post-polycondensation step: To further increase the molecular weight, the product obtained in the pre-polycondensation step was first heated to 270°C in a reaction vessel under nitrogen protection and normal pressure, and then the pressure was reduced to 30 Pa and the reaction was continued for 4 hours. After the reaction, the polyamide resin was obtained by cooling to room temperature.

[0046] Example 4

[0047] The preparation method of aliphatic long carbon chain copolyamide resin containing oxalamide component comprises the following steps:

[0048] (1) Pre-condensation step: A mixture of 86.2 g (0.5 mol) of decanediamine, 115.2 g (0.5 mol) of dibutylene oxalyl and 230 g (1 mol) of dodecanedioic acid was added to a reaction vessel, and 0.55 g of sodium hypophosphite and 0.34 g of antioxidant 1010 were added at the same time. After replacing with nitrogen, the temperature was raised under nitrogen protection and stirred at normal pressure to react. The temperature was controlled at 160°C and the reaction was continued for 3 hours.

[0049] (2) Post-polycondensation step: To further increase the molecular weight, the product obtained in the pre-polycondensation step was heated to 260° C. in a reaction vessel under nitrogen protection and normal pressure, and the reaction was continued for 4 h. After the reaction, the product was cooled to room temperature to obtain a polyamide resin.

[0050] Example 5

[0051] The preparation method of aliphatic long carbon chain copolyamide resin containing oxalamide component comprises the following steps:

[0052] (1) Pre-polycondensation step: A mixture of 137.9 g (0.8 mol) of decanediamine, 56.5 g (0.2 mol) of oxalyldicyclohexanediamine and 258.4 g (1 mol) of tetradecanedioic acid was added to a reaction vessel, and 13.6 g of sodium hypophosphite was added at the same time. After replacing with nitrogen, the temperature was raised under nitrogen protection and stirred at normal pressure to react. The temperature was controlled at 160° C. and the reaction was continued for 5 hours.

[0053] (2) Post-polycondensation step: To further increase the molecular weight, the product obtained in the pre-polycondensation step is first heated to 280°C in a reaction vessel under nitrogen protection and normal pressure, and then the pressure is reduced to 30 Pa and the reaction is continued for 6 hours. After the reaction, the polyamide resin is obtained by cooling to room temperature.

[0054] Example 6

[0055] The preparation method of aliphatic long carbon chain copolyamide resin containing oxalamide component comprises the following steps:

[0056] (1) Pre-condensation step: A mixture of 80.1 g (0.4 mol) of dodecanediamine, 171.9 g (0.6 mol) of dihexamethylenediamine oxalyl and 230 g (1 mol) of dodecanedioic acid was added to a reaction vessel, and 0.58 g of potassium phosphite was added at the same time. After replacing with nitrogen, the temperature was raised under nitrogen protection and stirred at normal pressure to react. The temperature was controlled at 140° C. and the reaction was continued for 3 h.

[0057] (2) Post-polycondensation step: To further increase the molecular weight, the product obtained in the pre-polycondensation step was heated to 240°C in a reaction vessel under nitrogen protection and normal pressure, and then the pressure was reduced to 30 Pa and the reaction was continued for 3 hours. After the reaction, the polyamide resin was obtained by cooling to room temperature.

[0058] Example 7

[0059] The preparation method of aliphatic long carbon chain copolyamide resin containing oxalamide component comprises the following steps:

[0060] (1) Pre-condensation step: A mixture of 121.1 g (0.65 mol) of undecanediamine, 90.4 g (0.35 mol) of dipentanediamine oxalyl and 216.3 g (1 mol) of undecanediic acid was added to a reaction vessel, and 0.86 g of sodium hypophosphite was added at the same time. After replacing with nitrogen, the temperature was raised under nitrogen protection and stirred at normal pressure to react. The temperature was controlled at 150° C. and the reaction was continued for 2 h.

[0061] (2) Post-polycondensation step: To further increase the molecular weight, the product obtained in the pre-polycondensation step was heated to 250°C in a reaction vessel under nitrogen protection and normal pressure, and then the pressure was reduced to 50 Pa and the reaction was continued for 3 hours. After the reaction, the polyamide resin was obtained by cooling to room temperature.

[0062] Example 8

[0063] The preparation method of aliphatic long carbon chain copolyamide resin containing oxalamide component comprises the following steps:

[0064] (1) Pre-condensation step: A mixture of 68.9 g (0.4 mol) of decanediamine, 205.5 g (0.6 mol) of dioctyl oxalyldiamine and 244.3 g (1 mol) of tridecanedioic acid was added to a reaction vessel, and 0.93 g of sodium hypophosphite was added at the same time. After replacing with nitrogen, the temperature was raised under nitrogen protection and stirred at normal pressure to react. The temperature was controlled at 140° C. and the reaction was continued for 4 hours.

[0065] (2) Post-polycondensation step: To further increase the molecular weight, the product obtained in the pre-polycondensation step was heated to 230° C. in a reaction vessel under nitrogen protection and normal pressure, and the reaction was continued for 4 h. After the reaction, the product was cooled to room temperature to obtain a polyamide resin.

[0066] Example 9

[0067] The preparation method of aliphatic long carbon chain copolyamide resin containing oxalamide component comprises the following steps:

[0068] (1) Pre-condensation step: A mixture of 51.7 g (0.3 mol) of decanediamine, 200.5 g (0.7 mol) of dihexamethylenediamine oxalyl and 202.2 g (1 mol) of decanediic acid was added to a reaction vessel, and 0.93 g of hypophosphorous acid was added at the same time. After replacing with nitrogen, the temperature was raised under nitrogen protection and stirred at normal pressure to react. The temperature was controlled at 170°C and the reaction was continued for 4 hours.

[0069] (2) Post-polycondensation step: To further increase the molecular weight, the product obtained in the pre-polycondensation step was heated to 270°C in a reaction vessel under nitrogen protection and normal pressure, and then the pressure was reduced to 30 Pa and the reaction was continued for 6 hours. After the reaction, the polyamide resin was obtained by cooling to room temperature.

[0070] Example 10

[0071] The preparation method of aliphatic long carbon chain copolyamide resin containing oxalamide component comprises the following steps:

[0072] (1) Pre-polycondensation step: A mixture of 51.7 g (0.3 mol) of decanediamine, 200.5 g (0.7 mol) of dihexamethylenediamine oxalyl and 230 g (1 mol) of dodecanedioic acid was added to a reaction vessel, and 0.92 g of phosphoric acid was added at the same time. After replacing with nitrogen, the temperature was raised under nitrogen protection and stirred at normal pressure to react. The temperature was controlled at 170° C. and the reaction was continued for 3.5 hours.

[0073] (2) Post-polycondensation step: To further increase the molecular weight, the product obtained in the pre-polycondensation step was heated to 270°C in a reaction vessel under nitrogen protection and normal pressure, and then the pressure was reduced to 30 Pa and the reaction was continued for 5 hours. After the reaction, the polyamide resin was obtained by cooling to room temperature.

[0074] Embodiment 11

[0075] The preparation method of aliphatic long carbon chain copolyamide resin containing oxalamide component comprises the following steps:

[0076] (1) Pre-condensation step: A mixture of 103.4 g (0.6 mol) of decanediamine, 114.6 g (0.4 mol) of dihexamethylenediamine oxalyl and 258.4 g (1 mol) of tetradecanedioic acid was added to a reaction vessel, and 0.67 g of sodium hypophosphite was added at the same time. After replacing with nitrogen, the temperature was raised under nitrogen protection and stirred at normal pressure to react. The temperature was controlled at 160° C. and the reaction was continued for 3 h.

[0077] (2) Post-polycondensation step: To further increase the molecular weight, the product obtained in the pre-polycondensation step was first heated to 270°C in a reaction vessel under nitrogen protection and normal pressure, and then the pressure was reduced to 50 Pa and the reaction was continued for 3 hours. After the reaction, the polyamide resin was obtained by cooling to room temperature.

[0078] Comparative Example 1

[0079] PA1012 resin product from Arkema of France is commercially available.

[0080] Comparative Example 2

[0081] PA1010 resin product from Eiseman Company is commercially available.

[0082] Comparative Example 3

[0083] PA6 resin products from Arkema of France are commercially available.

[0084] Experimental test case

[0085] 1) Relative viscosity η of aliphatic long carbon chain copolyamide resin containing oxalamide component r It is prepared with 96% concentrated sulfuric acid as solvent to a solution with a concentration of 1.0g / dl and measured with an Ubbelohde viscometer at 25°C.

[0086] 2) The tensile properties were tested according to GB / T1040-92 test standard using a CMT4104 universal material testing machine (Shenzhen Xinsansi Material Testing Co., Ltd.) at a tensile rate of 50.0 mm / min -1 .

[0087] 3) The water absorption performance is tested in accordance with GB / T 1034 test standard, and the samples are immersed in a constant temperature water bath at 23±1℃ for 24±1h.

[0088] 4) The heat deformation temperature is tested according to GB / T 1634.2 test standard. The heat deformation temperature A is obtained under a load of 1.80 MPa bending stress, and the heat deformation temperature B is obtained under a load of 0.45 MPa bending stress.

[0089] Table 1 Product test results of Examples 1 to 11 and Comparative Examples 1 to 3

[0090]

[0091]

[0092] As can be seen from Table 1, the aliphatic long carbon chain copolyamide resin of the present invention, by introducing oxalamide components into conventional long carbon chain polyamide resins, has, on the one hand, yield strength and heat resistance superior to those of conventional long carbon chain polyamide resins, while retaining the low water absorption rate of long carbon chain polyamide resins; on the other hand, it has mechanical strength and heat resistance comparable to or superior to those of PA6 resin, while having better stretchability and lower water absorption.

Claims

1. An aliphatic long carbon chain copolyamide resin containing an oxalamide component, characterized in that: The raw materials include long-chain diamine, oxalyl diamine and long-chain dicarboxylic acid, wherein the molar ratio of the long-chain diamine to the oxalyl diamine is (30-80):(70-20), and the ratio of the total molar number of the long-chain diamine and the oxalyl diamine to the molar number of the long-chain dicarboxylic acid component is 1:1; The long carbon chain diamine is at least one of the straight chain diamines with carbon atoms of 10 to 12; the oxalyl diamine is at least one of the diamines containing the oxalamide structure [-HN-(C=O)-(C=O)-NH-]; and the long carbon chain dicarboxylic acid is one or two of the straight chain dicarboxylic acids with carbon atoms of 10 to 14.

2. The aliphatic long carbon chain copolyamide resin according to claim 1, characterized in that: The oxalyl diamine is at least one of dibutylene oxalyl diamine, dipentylene oxalyl diamine, dihexylene oxalyl diamine, dioctylene oxalyl diamine, didecylene oxalyl diamine or dicyclohexylene oxalyl diamine.

3. The aliphatic long carbon chain copolyamide resin according to claim 1, characterized in that: Relative viscosity η at 25°C r The thermal deformation temperature under the bending stress of 1.80MPa and 0.45MPa is 58.0~71.5℃ and 164.5~174.0℃ respectively.

4. The method for preparing the aliphatic long carbon chain copolyamide resin according to any one of claims 1 to 3, characterized in that: The mixture of the long carbon chain diamine, the oxalyl diamine and the long carbon chain dicarboxylic acid is subjected to a polycondensation reaction in a staged or continuous manner, including a pre-polymerization step and a post-polymerization step; The pre-polymerization step The method comprises the following steps: adding a mixture of a long carbon chain diamine, oxalyl diamine and a long carbon chain dicarboxylic acid into a reactor, adding an amidation catalyst at the same time, heating and stirring under normal pressure under nitrogen protection, and reacting at a temperature of 110 to 170° C. for 2 to 5 hours; The post-polymerization process includes the following steps: under nitrogen protection and normal pressure conditions, heating the product of the previous polycondensation process in a reactor to a set temperature for continuous reaction, and cooling to room temperature after the reaction to obtain a polyamide resin; the set temperature is 180 to 300° C.; and the continuous reaction time is 1 to 12 hours.

5. The method for preparing the aliphatic long carbon chain copolyamide resin according to claim 4, characterized in that: In the post-polymerization process, the set temperature is 200-280° C.; the continuous reaction time is 2-9 hours.

6. The method for preparing the aliphatic long carbon chain copolyamide resin according to claim 4, characterized in that: The post-polymerization step is carried out under reduced pressure, and the pressure reached by the reduced pressure polymerization is 10 to 1000 Pa.

7. The method for preparing the aliphatic long carbon chain copolyamide resin according to claim 4, characterized in that: The preparation method of oxalyl diamine comprises the following steps: under nitrogen protection and stirring, dripping an ethanol solution of diethyl oxalate into an ethanol solution of butanediamine, pentamethylenediamine, hexamethylenediamine, octanediamine, decanediamine or cyclohexamethylenediamine, heating and refluxing for 8 hours after dripping, washing the filter cake obtained by filtration with ethanol and water in turn, and drying to obtain a white oxalyl diamine component; wherein the molar ratio of the diamine to the oxalic acid diester is 3:

1.

8. The method for preparing the aliphatic long carbon chain copolyamide resin according to claim 4, characterized in that: The amidation catalyst is at least one of potassium hypophosphite, sodium hypophosphite, magnesium hypophosphite, calcium hypophosphite, zinc hypophosphite, potassium phosphite, sodium phosphite, magnesium phosphite, calcium phosphite, zinc phosphite, potassium phosphate, magnesium phosphate, calcium phosphate, zinc phosphate, hypophosphorous acid, phosphorous acid and phosphoric acid; the addition amount of the amidation catalyst is 0.05-0.3% of the total mass of the mixture.

9. The method for preparing the aliphatic long carbon chain copolyamide resin according to claim 4, characterized in that: The auxiliary agent is added during or after the polycondensation reaction, and the auxiliary agent includes a flame retardant, an antistatic agent, an antioxidant, a light stabilizer, a colorant, an ultraviolet absorber, an antibacterial agent and / or a crystallization accelerator.

10. The molded article of the aliphatic long carbon chain copolyamide resin according to any one of claims 1 to 3, characterized in that It is processed into any shape of sheet, film, fiber, wire, tube, regular or irregular block by injection, extrusion, blow molding, hollow, hot pressing, casting or / and foaming.

11. The molded article of the aliphatic long carbon chain copolyamide resin according to claim 10, characterized in that: Used in automotive industry parts, electronic and electrical equipment, optical equipment parts, information and communication equipment, construction industry supplies, medical device industry parts, packaging materials supplies, national defense and military equipment parts, media transportation supplies, and household products.

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