JPS58120665A - Underhood parts for cars - Google Patents

Abstract

PURPOSE:A composition that is made by combining a polyamide which contains specific aliphatic and aromatic components and keeps crystalline with, when necessary, an inorganic reinforcing material, thus having high resistance to a road surface antifreezer as well as toughness and heat resistance. CONSTITUTION:100pts.wt. of a crystalline polyamide consisting of components selected from 4-8C aliphatic lactams, aminoacids, diamines and dicarboxylic acids and aromatic components of the formula [X, Y are -(CH2)m-NH2, -(CH2)n- COOH; R is 1-4C alkyl, halogen, l is 1-4; m is 1-3; n is 0-2], e.g., a copolymer of p-aminomethylbenzoic acid and epsilon-caprolactam or a mixture thereof with less than 80wt% aliphatic polyamide are mixed with 0-100pts.wt. of an inorganic reinforcing material such as glass fiber, carbon fiber, talc. Then, the resultant composition is molded to give underhood parts for cars.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an automobile made of polyamide, which has good resistance to road surface antifreeze agents containing metal halide compounds such as carnoum chloride and zinc chloride as main ingredients, and has excellent rigidity and heat resistance. This relates to Anogoo hood parts.

Recently, there has been a noticeable trend in the automobile industry to replace conventional metal parts with resin for purposes such as weight reduction, rust prevention, and sound insulation to improve fuel efficiency. Among them, polyamide resin has characteristics such as excellent heat resistance, oil resistance, moldability, and toughness, so it is used in automobile underhood parts such as cooling fans, radiators, tops and bases of air conditioners, Applications to various functional parts such as bars, oil pumps, gears, valves, brake piping, fuel piping tubes, other exhaust gas system parts, and electrical system parts such as connectors are attracting attention.

However, polyamides with a relatively high concentration of amide groups, such as nylon 6 and nylon 66, which are commonly used among polyamide resins, inherently have a strong affinity for inorganic metal salts such as calcium chloride and zinc chloride. Therefore, underhood parts for automobiles made of these materials have the serious drawback of being attacked by metal salts such as carnoum chloride, magnesium chloride, and zinc chloride, and cracking occurs within a short period of time. In general, large amounts of antifreeze agents containing calcium chloride, magnesium chloride, etc. are sprayed on roads in cold regions to prevent road surfaces from freezing, especially in winter. If it adheres to the underhood parts of a certain automobile, it will cause cracks in the parts, and there is a high risk of causing a car accident.

Therefore, although automobile underhood parts made of nylon 6, nylon 66, etc. have excellent strength and heat resistance, and are inexpensive, their use is limited due to insufficient resistance to road deicing agents. Therefore, there is a long-awaited expectation for the emergence of low-grade polyamide-based materials that are resistant to road deicing.

Therefore, the present inventors investigated polyamide-based underhood parts for automobiles that satisfy required properties such as resistance to road antifreeze agents, rigidity, toughness, heat resistance, and chemical resistance. Contains aromatic components,
Anotar hood parts for automobiles in which an inorganic reinforcing material is blended as necessary with a polyamide retaining crystalline t/+ or a mixture of the polyamide and a normal aliphatic polyamide, and the composition has extremely irregular physical properties. It was found that it gave 1.

(2) At least one component selected from aliphatic lactams, amino acids, diamino and dicarboxylic acids having 4 to 8 carbon atoms and an aromatic component represented by the following formula are combined in 4 barrels. 100 parts by weight of crystalline polyamide or a mixture thereof with 80% by weight or less of Bl aliphatic polyamide and +C1 inorganic reinforcing material 0 to 100 parts by weight
Automotive underhood parts made by molding a compound consisting of heavy trenches.

Here, x, y: ICH, 3+I=, NH, or ICH
2 C00HR: C, ~C4 alkyl group or halogen e; integer of 1 to 4 m: integer of 1 to 3 n: integer of 0 to 2 The polyamide used in the present invention is a fatty acid having 4 to 8 carbon atoms. At least one component selected from group lactams, amino acids, diamino Jj and dicarboxylic acids, such as ε-
Caprolactam, tetramethyleneamine, hexamethylenediamino, adipic acid, etc. and aromatic components represented by the above formulas, such as para-aminomethylbenzoic acid, /maraminoethylbenzoic acid, terephthalic acid, 2-methylterephthalic acid, 2.5- Jimechi J Reterefta Ishita, z, 5
- It is a polyamide that can be melted with dibromoterephthalic acid, puffed xylylene diamine, etc. as its main components, and maintains crystallinity. As for the other components, there are no particular limitations, and conventionally known polyamide-forming components can be used. Typical examples of these polyamides include co-polyamides of paraamine methylbenzoic acid and ε-caprolactam or hexamethylenediamine adipate (nylon PAMBA/6, PAMB
A/66), hexamethylenediamine terephtha/L
/ m Copolymer with salt ε-caglolactam or hexamethylenediamine adipi II (nylon 6T/6
．． 6T/66), copolymer of paraxylylenediamine adipate and ε-cabrofuctam or hexamethylenediamine adipate (nylon PXD 6/6)
, PXD6/66, etc., and it is also possible to use two or more polyamides together). All of the polyamides mentioned here are already well known, but they can be applied to the field of IJJ military underhood parts and have good resistance to metal halides such as calcium chloride. Moreover, it has not been known in the past that 11]11 properties, heat resistance, toughness, chemical resistance, etc. can be obtained. In other words, the feature of the present invention is that the polyamide whose main constituents are a specific aliphatic component and an aromatic component has a very high amide concentration (the number of amide groups per the number of carbon atoms t) that is not much different from ordinary nylon 6 or nylon 66. However, this material is based on the new knowledge that it has extremely good resistance to metal halides (1). The production conditions for the Al crystalline polyamide used here are
The polymer can be obtained at a temperature of 550'C by a suitable combination of pressure, pressure and reduced pressure operations.

(As for the synthetic skin of Al crystalline polyamide, there is no particular restriction, and any polyamide whose normal relative viscosity is within the range of 1.7 to 4.5 can be selected.
Although the crystalline polyamide can be used alone, it can also be used as a mixture with 80% by weight or less of other CB+aliphatic polyamides.

(El aliphatic polyamides used in the invention) include polycaproamide (nylon 6), polyhexamethylene adipamide (nylon 6lon), polyhexamethylene dodecamide (nylon 61o), polyhexamethylene dodecamide (
Nylon 612), polyunatecamethylene adivamide (Nylon 116), polyundecaneamide (Nylon 11, polyundecaneamide (Nylon 12), and co-combined polyamides thereof, etc., and the above-mentioned polyamides with 2 or more rods are used in combination. It is also possible to do so.The degree of consistency of the CB1111 ILL & polyamide used here is not particularly limited, and usually a polyamide with a viscosity of 2.0 to 5 degrees can be selected. .

(c) The inorganic reinforcing material used in the invention is glass fiber,
Asbestos fiber, carbon fiber, calcium acetate, talc,
Examples include magnesium uride, aluminum oxide, wollastenite, micro-M mica, granular glass, and potassium titanate whiskers.

The underhood parts for automobiles of the present invention are made of fAJAl crystalline polyamide containing specific aliphatic components and aromatic components, and a mixture of this and ordinary (Bl aliphatic polyamide) with 80% by weight or less, more preferably 75% by weight or less. It can be obtained by molding a composition comprising parts by weight of the inorganic reinforcing material (C) and 0 to 100 parts by weight, more preferably 0 to 90 parts by weight.

Here (the amount of Bl 1111 fatty acid polyamide used is 8,
If it exceeds 0% by weight, the resistance to metal halides will be noticeably reduced, and it may not be possible to obtain automotive underhood parts with excellent road antifreeze properties, or -U properties, Hu
It is undesirable because the purpose of metal replacement cannot be achieved due to insufficient thermal properties. In addition, if the amount of inorganic reinforcing material added to 100 parts of polyamide exceeds 100 parts, it will be rather strong.
It is undesirable because it has low strength and becomes brittle, impairing its function as an automatic military underhood part.

Special? Inorganic reinforcement is not required when obtaining such flexible parts.

iAI JE component polyamide, (B) component polyamide, and (C) inorganic reinforcing material blending method There are no particular restrictions. After mixing, a method of melt-kneading in an extruder with sufficient kneading capacity, a method of tri-blend injection or extrusion molding, etc. can be used.

The underhood parts for automobiles of the present invention are molded by subjecting the polyamide 18 compound to general thermoplastic resin molding methods such as injection molding, extrusion molding, glow molding, and vacuum molding. Injection molding or extrusion molding 1 Cooling fans, radiator tanks, cylinder head covers, oil pans, gears, pulp, brake piping, fuel piping, other tubes, pipes, other exhaust gas system parts, connectors, etc.゛Electrical components, notebooks, etc. are useful.

Note that the molded part thus obtained can also be subjected to primary processing such as painting, vapor deposition, and bonding.

In addition, the underhood parts for automobiles of the present invention may contain other ingredients such as pigments, dyes, heat resistant agents, antioxidants, 11 additives, lubricants, and stiffeners, as long as they do not impair their moldability or physical properties. Nucleating agents, antistatic agents, plasticizers, other polymers, etc. can be added and introduced.In particular, the present inventors have already proposed 11111 road antifreeze polymers with poor properties, such as ethylene-based polymers. If an ionomer resin or the like is added for the purpose of imparting more flexibility, it is possible to obtain underhood parts for self-excited vehicles with no practical value.

The present invention will be described in more detail below with reference to specific examples. In addition, the physical properties of the test specimens tested in the Taitane example were measured in accordance with the following method 1.

(1) Relative viscosity: J Engineering S [6810L2J
Tensile test: ASTM D65B (3) Bending test: ASTkA D790 (4) Izod impact test: ASTM D256 (5) Metal halide resistance test, after immersing the underhood molded product in 90 °C hot water for 24 hours, 100 °C While the gear is open, leave it as it is, spray 5096 chloride liquid in the form of water droplets every hour for one cycle, and measure the cycle/I/resistance until cracks appear on the molded product. did.

(6) Crystallinity: Perkin Elnoer DSC
When the sample was heated at 11 times under the conditions of 0° C./min according to company regulations, SC1B type, crystallinity was evaluated based on the appearance of a clear one-resolution absorption peak (one point) and a crystallization exothermic peak (crystallization point).

Example 1 Hexamethylene diamine taffle punching tomo JX/
A copy of 50 violet salt and 1 adipic acid hexamethylenediamine 7GB (obtained by melt-polymerizing 1 piece of electric wire, relative viscosity 2.50, melting point 270°C, crystallization temperature 225
℃ Nylon 6T/66 (50/70) Co-arashi combination +1
Add 45 parts by weight of Tai Chopped Strand Glass Fiber TP-24 from Nippon Glass Fiber Co., Ltd. to 1 part by weight of 00i, mix uniformly with a high-speed I stirrer, and melt with a 65II 11φ diameter extruder. After kneading, the mixture was pelletized.

After vacuum drying the pellets, A8T was molded into the injection molding machine under conditions of a cylinder temperature of 290°C and a mold temperature of 80°C.
M standard physical property test piece, length 450s+++, width 20
0m+, height 80w1, wall thickness! A box-shaped cylinder head cover of L5m11 was molded.

When the molded pieces obtained here were examined for mechanical properties and resistance to metal halides, it was found that they exhibited extremely excellent properties as shown below.

Pull @ gi 1,800 kg/cm" Bending ground K 2,600 kg/32 Bending elasticity "4
A 1oao(+o kg/a+”Izot impact strength 9.0kg-alI/611 notch 1
lIit Calcium Chloride No cracking occurs even after testing for 10 cycles or more.

Example 2 Nylon 66:50% by weight with a relative viscosity of 2.90 obtained by melt polymerizing equimolar salts of hexamethylene diamine and adipic acid and nylon 6T/66 (5077
G) Copolymer: After adding 45 parts by weight of the same glass fiber as in Example 1 to 100 parts by weight of a 50% by weight mixture, kneading with an extruder and injection molding were performed in the same manner as in Example 1 to obtain A8.
A TM standard physical property test piece and a box-shaped cylinder head cover were prepared.

When the mechanical properties and resistance to metal halide of the molded piece obtained here were examined, it was found that it exhibited extremely excellent properties as shown below.

Tensile strength tyoo Wood/12 bending*leather 2,500 kg△1 bending modulus
92,000 kg/ex"Izo impact strength 9.5 kg-ex/ax notch chloride resistance psium resistance 10 cycles or more Comparative example 1 *Amount of nylon bb 2 1 oazg part 4 gaff fiber 45' iL used in flow side 2 When the cylinder head cover obtained by injection molding in the same manner as in Example 1 was examined for chloride resistance p-sium, undefeated cracks occurred on the entire surface of the molded product in just the first cycle.

Example 5 Relative viscosity of 2.4 obtained by melting and placing ω-foulofuctam
0 nylon 12:601! [Fumoto% and nylon 6T/66 (50/7C1) used in Example 1] Combined with a plate: 45 liters of the same glass fiber as in Example 1 for 100 liters of the 40 liters mixture After addition, the mixture was strained, extruded, molded, and injection molded in the same manner as in Example 1 to prepare a physical property test piece of A8TM standard and a box-shaped cylinder head cover.

When the in-situ physical properties and resistance to metal halides of the molded piece obtained here were examined, it was found that it exhibited extremely excellent properties as shown below.

Tensile strength 1,600 kg/a' Bending strength 2.500 kg/α2 Flexural modulus 81.000 kg/ex Izot impact strength 1α2 1/1 notch chloride resistance l Lesium resistance 1a psi or more Comparative example 2 Implementation 100 parts by weight of the nylon 12 used in Example 5, 100 parts by weight of glass carpet, and 100 parts by weight of T45 were combined and injection molded in the same manner as in Example 1.The physical properties of the test piece obtained were as follows. However, as a metal substitute material, its strength and rigidity were unsatisfactory.

Bending strength: 1,400 kg/cII2 Flexural modulus: 44,000 kg/cm” Examples 4 to 1
0 The properties of the test pieces and underhood parts prepared by changing the polyamide composition, the inorganic refrigerating material, the content, etc., and performing the same operations as in Example 1 are shown in Table 1. Got the results.

It has been found that molded articles having extremely excellent properties can be obtained in all cases shown in Table 1.

! iIi! Example 11 Equimolar salt of sameethylene diamine and terephthalic acid on the downstream side 60
Nylon 6T/6 (60/40) with a relative viscosity of 2.4 Q, a melting point of 257°C, and a concentration of 182°C, obtained by melt polymerizing a mixture of 1 part of mJ and 40 parts of ε-force block tom.
) 80% by weight of copolymer 2 and undecamethylenediamine.
Relative viscosity 2 obtained by melt polymerization of equimolar lv salt of adipic acid
．． 75 nylon 116: 20% by weight homogeneous mixture of 4
5 After feeding into a tube extruder with a diameter of φ, extrude it into a cylindrical shape at 270℃ through an internal pressure tube forming die and cool it in water at 5℃ through a sizing grate.1
A tube molded product with a wall thickness of 61 g was obtained.

The tube obtained here was placed in 80℃ hot water for 11 hours for 24 hours.
The treated steel was immersed in a 5096 zinc chloride water bath solution at 23°C with a strict inner bending radius of 10 sul, and then subjected to a model μ test of a road anti-freeze agent.
Even after 00 hours had elapsed, no cracks were observed at all.

Claims (1)

[Claims] (2) An aliphatic lactam having 4 to 8 carbon atoms, an amino acid,
100 parts by weight of a crystalline polyamide whose main constituents are at least one component selected from diamino and dicarboxylic acids and an aromatic component represented by the following formula, or a mixture thereof with 80% by weight or less of a 6-aliphatic polyamide; (C) An underhood part for an automobile formed by molding a compound containing 0 to 100 parts by weight of an inorganic reinforcing material. where X and Y (C12iNH2 or -(C
H2,i C00H R: C, ~C4 alkyl group or halogen e: 1~
For integer m of 4 to integer n of 3: integer of O to 2