JPS6346221A - Heat-resistant polyamide - Google Patents

Abstract

PURPOSE:To provide the titled novel polymer having a specific structure and a controllable glass transition point and injection moldable while keeping high heat-resistance owing to the selectability of the combination of the glass transition point and heat-resistance over a wide range. CONSTITUTION:The objective polymer is composed of the structure of formula I [X is group of formula II (R is H, CH3, etc.); Y is group of formula III or IV (n is integer of 2-6); m is number of recurring units] wherein the ratio of the unit of formula II in the component Y is 1-99mol% and that of the unit of formula III is 99-1mol%. It has an intrinsic viscosity etainh of >=0.25dl/g measured at 30 deg.C as a solution produced by dissolving the polymer in dimethylacetamide at a concentration of 0.5g/100ml. The polymer can be produced e.g. by reacting a 9,9-bis(4-aminophenyl)fluorene compound with a mixture of terephthalic acid chloride and adipic acid chloride constituting the component Y in a solvent such as dimethylacetamide.

Description

[Detailed description of the invention] Industrial application field The present invention is a novel copolyamide, which is characterized by heat resistance and moldability, and can be used as a material for fibers, films, and injection molded products. Regarding polyamide.

Aramid, which is a fully aromatic polyamide fiber representative of conventional technology, has a long-term heat resistance temperature of about 220° C. and is known as a useful polyamide that forms high-strength fibers.

However, in order to make this 7-lamid into fibers, it is first necessary to make it into a solution. There is. This causes suspended lithium chloride and calcium chloride to clog the pipes, causing equipment failure and other problems in production.

In addition, when producing molded products, injection molding is difficult due to their high heat resistance, and even if they are generally highly rotary, problems remain in the processing surface.

Korshak et al., Journal of Macromolecules, Sci.
, Rev.

Macromol, Chew, , C month, 45.1
(1974) reported on soluble polyamides, but there has never been an example of improving injection moldability while maintaining high heat resistance.

Problems to be solved by the invention Adding solubility to synthetic resins also leads to improved processability, but in this case, the range of use is limited to fibers, films, etc.0 It is difficult to mold and process synthetic resins. Injection molding is a method with a wide range of applications, but in this case, the heat resistance of the synthetic resin used is a problem.

If the heating temperature during injection molding is set to a high temperature, the synthetic resin will undergo thermal decomposition, leading to a decrease in the physical properties of the molded product.In general, the lower limit of the molding temperature for crystalline synthetic resins is set at the melting point (T+
It is said that it is good to be about 30°C higher than w), and about 100°C higher than the glass transition point (Tg) for non-grade polymers. In both cases, the synthetic resin temperature during injection molding is
It must be carried out at a temperature approximately 50° C. or more lower than the thermal decomposition temperature of the synthetic resin.

In other words, the upper limit of heating temperature in on-machine injection molding is 4
If it is 00°C, the upper limit for T+a is 370°C for crystalline polymers, and 300°C for amorphous polymers.

The present invention aims to provide a polyamide whose glass transition point can be controlled, which can satisfy the above conditions depending on the injection molding conditions, and which has the necessary heat resistance. .

Means for solving the problem, that is, the present invention provides a polyamide having a structural formula of the formula (NH-X-NH-Y)m (however, the number of repeating units in the layer) is a polyamide containing any of C2H5. ), consisting of GO- (where n is a positive integer of 2 to 6), and the composition ratio of (B) and (C) in the Y component is 1 to 98 mol% (B). (C) 99 to 1 mol%, and the polyamide 0
．． The intrinsic viscosity (η1nh) of a solution prepared by dissolving 5 g of dimethylacetamide at 30°C is o.
, 25 dQ/g or more.

The polyamide of the present invention has a structure with an amide bond obtained by dehydration condensation of a diamine and a dicarboxylic acid +NH-X-
NH-Y')m. In this case, the diamines used as raw materials for X include 9,9-bis(4-aminophenyl)fluorene, 9,9-bis(3-methyl-4-7
Minophenyl)fluorene and 9,9-bis(3-ethyl-4-7minophenyl)fluorene can be used. A indicates the residue of the diamine excluding the amine groups at both ends.

In addition, the dicarboxylic acids that serve as raw materials for Y include aromatic dicarboxylic acids (the residues excluding the hydroxyl groups at both ends are B),
Aliphatic dicarboxylic acid (residues excluding hydroxyl groups at both ends are C
The aromatic dicarboxylic acid is preferably terephthalic acid or inphthalic acid, and the aliphatic dicarboxylic acid is a dicarboxylic acid that can easily obtain the desired glass transition temperature, such as succinic acid with n of 2 to 6 (n=2 ), glutaric acid (n=3), adipic acid (n=4), pimelic acid (n=
5) and superic acid (n=6), and more preferably B is a terephthalic acid residue and C is a combination of an adipic acid residue where n is 4.

Furthermore, in the formula, Y consists of chain members B and C, and preferably the molar ratio B:C is from 1:99 to 99:1, more preferably from 5:95 to 95:5; The glass transition temperature of polyamide is the glass transition temperature that allows injection molding! The temperature is 35°C to 350°C. 13 more
A glass transition temperature of 0 or more is preferably a glass transition temperature of 5 DEG C. to 300 DEG C., as mentioned above, is a suitable temperature range for injection molding. That is, the value is selected by taking into account the capabilities of the current injection molding machine. The polyamide is B,
A major feature is that these can be accommodated by selecting the blending ratio of C.

In the polyamide of the present invention, 0.5 g of the polyamide
dimethylacetamide + 00. d solution dissolved in 3
Intrinsic viscosity (η1nh) measured at 0℃ is 0.25dQ
7 g or more, preferably 0.30 dQ/g or more,
More preferably, it is 0.35 dQ/g or more.

If the value of intrinsic viscosity is small, when the polyamide is made into a film or a molded product, it is difficult to mold it and the molded product becomes brittle. Moreover, the decomposition temperature also decreases by 1 g, resulting in poor heat resistance.

Also, heat is inevitably applied during injection molding, but
It is well known that aromatic amines, that is, aniline derivatives, are very easily oxidized, and the terminal aniline group of the polyamide is also easily oxidized, so the number of moles of dicarboxylic acid (raw material for Y) used during polymerization is reduced. By making the number of moles used slightly larger than the number of moles used of diamine (raw material of This terminal amino group may be protected, for example by reacting the terminal amino group with preferably an alkyl halide or an acyl halide, more preferably an acyl halide, most preferably an acetyl halide or a benzoyl halide. Convert to amide group. As a result, discoloration due to oxidation could be significantly prevented. Furthermore, this polyamide solution showed almost no coloration even after long-term storage.

The polyamide can be synthesized, for example, as follows. That is, 9.9-bis(4-aminophenyl)fluorenes are dissolved in a solution of a solvent such as dimethylacetamide, and 3 The desired polyamide can be obtained by reacting for about a period of time. However, the synthesis method is not limited.

In addition, the polyamide is soluble not only in injection molding but also in various solvents, and can be sufficiently molded into films and fibers.

Examples Example 1 (terminal benzoylated case) 9.9-bis(
4-7minophenyl) 8.98 g of fluorene and 4.04 g of triethylamine were dissolved in 100 J of dimethylacetamide, and 2.03 g of terephthalic acid chloride was dissolved at 5°C.
was added in powder form. Then adipic acid chloride 1.83
g and stirred for 3 hours.

Furthermore, 0.5-benzoyl chloride was added, and the mixture was stirred at room temperature for 2 hours. Triethylamide 241M salt was filtered through a glass filter and poured into methanol to obtain a polymer. Dimethylacetamide and methanol were added and the product was purified by reprecipitation twice.

Furthermore, the reaction was carried out by changing the molar ratio of terephthalic acid chloride and adipic acid chloride. The results are summarized in Table 1. However, cases where only adipic acid chloride and only terephthalic acid chloride were used were listed as comparative examples.

In Example 1, adipic acid/terephthalic acid = 9/1
The tensile strength of the polyamide is 9.5 kgf/mm', the tensile modulus is 450 kgf/mrn', and the volume resistivity is 9×1O1.
sΩcm, and the total light transmission amount was 90.8%.

Example 2 (case where terminals were not treated) The same procedure as in Example 1 was carried out without adding benzoyl chloride. The viscosity, Tg, and decomposition temperature were the same for both.

(Left below) Effects of the Invention The polyamide of the present invention has a wide range of combinations of glass transition temperature and heat resistance, and since combinations can be selected from among them as necessary, the molding method is not limited, and the range of use is greatly expanded. We can expect that.

In other words, most molding methods such as injection molding, fiber, and film are now possible, making it possible to use electricity, which has traditionally been used.
Applications are expanding beyond electronic parts and mechanical fields to new fields, especially fields that require heat resistance, and are useful for industrial development.

Claims (2)

[Claims] (1) A polyamide with the structural formula -(NH-X-NH-Y)-m (where m is the number of repeating units), where X is (A) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼(However, R
indicates either H, CH_3, or C_2H_5. ), and Y stands for (B)▲There are mathematical formulas, chemical formulas, tables, etc.▼
and (C) -CO-CnH_2_n-CO- (where n is a positive integer of 2 to 6), and (B
) and (C) have a composition ratio of (B) 1 to 99 mol% and (C
)99 to 1 mol%, and 0.5 g of the polyamide
was dissolved in 100 ml of dimethylacetamide.
Intrinsic viscosity (ηinh) when measured at 0°C is 0.25
A heat-resistant polyamide with a dl/g or higher. (2) The mixing molar ratio of (B) and (C) is 5:95 to 95
The polyamide according to claim (1), which is within the range of :5.