JPH0362832B2 - - Google Patents

Description

[Detailed description of the invention]

<Industrial Application Field> The present invention relates to a method for treating polyester fibers, and its purpose is to provide a method for treating polyester fibers that dramatically improves the heat-resistant adhesion between the fibers and rubber. be. In particular, the present invention relates to a novel treatment method for improving the adhesion performance between reinforced polyester fibers and rubber when the polyester fiber reinforced rubber composite is used under high load and high temperature conditions. <Prior art> Polyester fibers, typified by polyethylene terephthalate fibers, have physical properties such as high strength and Young's modulus, low elongation and creep, and excellent fatigue resistance. It is widely used for applications such as reinforcing composites. However, compared to polyamide fibers such as nylon 6 and nylon 66, polyester fibers have poor adhesion to rubber, and ordinary adhesive treatments do not provide the necessary strength to fully demonstrate the physical properties of polyester fibers. Adhesive performance cannot be obtained. The main reason for this is thought to be that the hydrogen bonding capacity of ester bonds in polyester is smaller than that of amide bonds in nylon. For this reason, a method has been proposed in which the surface of polyester fibers is treated with a highly reactive compound such as an epoxy compound or an isocyanate compound to impart adhesive properties (for example, Japanese Patent Publication No. 55632/1983; 47-49768 [Japanese Patent No. 692769], etc.). However, when attempting to improve the adhesion of polyester fibers to rubber, the treated fiber material becomes hard, making molding difficult and reducing fatigue resistance. <Objective of the Invention> The present invention has been made against the background of the above circumstances, and an object of the present invention is to provide excellent performance in adhesion between polyester fiber and rubber, particularly in heat-resistant adhesion. It is in. <Configuration of the Invention> That is, the present invention provides: (1) A linear aromatic polyester fiber having the following general formula (A)
Treated with a pretreatment agent containing a cresol novolak type epoxy compound represented by and aqueous nylon (B), and then treated with a polyepoxide compound (C),
treated with a first treatment agent containing a blocked polyisocyanate compound (D) and a rubber latex (E),
Subsequently, the ethylene urea compound represented by the following general formula (F) and the above-mentioned cresol novolac type epoxy compound (A) were added to resorcinol-formalin-rubber latex (RFL) (F)/(A) = 40/60.
A method for treating polyester fibers, comprising treating with a second treating agent added at a weight ratio of ~80/20. [Here, R' is -O-(CH ₂ ) _-k Cl, -O-(CH ₂ ) _-l
OH or −[O−(CH ₂ ) _n −] _n OH, R″ is H, CH ₃ ,
C ₂ H ₅ , K, l and m are integers of 1 to 4, m is an integer of 1 to 5, a and b are integers of 1 to 5, and a+b≦6. ] [Here, R is an aromatic or aliphatic hydrocarbon residue, and n is 0, 1 or 2. When n=0, the terminal group is hydrogen. ] The present invention can be applied to any linear aromatic polyester, especially those having the general formula [n represents an integer of 2 to 6. ] A polyester having a repeating unit represented by the following as a main component is preferably used, and a polyester having as a main glycol component at least one type of glycol selected from ethylene glycol and tetramethylene glycol is particularly preferably used. The cresol novolac type epoxy compound used in the pre-treatment agent and second treatment agent for polyester fibers of the present invention is represented by the following general formula (A). [Here, R' is -O-(CH ₂ ) _k -Cl, -O-(CH ₂ ) _l -
OH or −[O−(CH ₂ ) _n −] _n ′OH, R″ is H, CH ₃ ,
_C2H5 , k, l, m are integers of 1 to 4, m' is an integer of 1 _to 5, a, b are integers of 1 to 5, and a+b≦6. ] Various compounds that satisfy the above (A) can be considered, but
Good results are obtained by using a material with a molecular weight of 1200 to 1300 and an epoxy value of 4.0 to 4.5 eq/Kg. Next, the water-soluble methyl nylon (B) used in the pretreatment agent of the present invention is made by adding a hydrophilic vinyl monomer to a solution of a polyimide resin and polymerizing it to make the polyamide resin water-soluble. Polyamide resins that are particularly soluble in alcohol, such as N-methoxymethylated nylon, called type 8 nylon,
Copolymerized nylon or the like may be used, but it can be obtained by adding 0.1 part or more of a hydrophilic vinyl monomer to 1 part of polyamide resin, adding a polymerization catalyst, and polymerizing by heating and stirring. The polyamide resin used in the present invention is an alcohol-soluble polyamide resin, for example, N-alkoxymethylated nylon such as N-methoxymethylated nylon, N-ethoxymethylated nylon, N-butoxymethylated nylon, copolymerized nylon, Examples include alcohol/calcium chloride soluble polyamide resins such as nylon 6 and nylon 66. Examples of the hydrophilic vinyl monomer include acrylic acid, methacrylic acid, hydroxyethyl acrylate, hydroxyethyl methacrylate, polyethylene glycol monomethacrylate, itaconic acid, acrylamide, N-methylolacrylamide, or mixtures thereof. As the polymerization catalyst, catalysts commonly used for carrying out radical polymerization reactions, such as azobisisobutyronitrile and benzoyl peroxide, may be used. Since the water-soluble nylon has carboxyl groups, hydroxyl groups, etc., it also reacts with epoxy groups. Specifically, for example, it is represented by the following chemical formula. This may be further grafted with acrylic acid, acrylamide, etc. to add a carboxyl group to make it water-soluble. Add the cresol novolac type epoxy compound mentioned above to this, or
Water-soluble nylon (B)/cresol novolac type epoxy compound (A) weight ratio (B)/(A) is 100/10 to 100/80
Blend with. In particular, it is preferable to mix them in a ratio of 100/10 to 10/50 (weight ratio). If (B)/(A) is out of the above range, the adhesion of water-soluble nylon to polyester fibers will be poor, resulting in decreased adhesion or hardness, resulting in decreased fatigue resistance. The total solids concentration including water-soluble nylon (B) and cresol novolak type epoxy compound (A) is 1 to 1% of the fiber weight.
The content is 30wt%, preferably 3 to 20wt%. If the concentration is too low, the adhesion will decrease, and if the concentration is too high, it will become hard and the fatigue resistance will decrease. The polyepoxide compound (C) used in the first treatment agent is a compound containing at least two or more epoxy groups in one molecule in an equivalent amount of 0.2 g or more per 100 g of the compound, and includes ethylene glycol, glycerol, sorbitol, pentaerythritol, Reaction products of polyhydric alcohols such as polyethylene glycol and halogen-containing epoxides such as epichlorohydrin, resorcinol, bis(4-hydroxyphenyl)dimethylmethane, phenol.
Reaction products of polyhydric phenols such as formaldehyde resins and resorcinol/formaldehyde resins with the halogen-containing epoxides, polyepoxide compounds obtained by oxidizing unsaturated compounds with peracetic acid or hydrogen peroxide, etc., i.e., 3,4- Epoxycyclohexene epoxide, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexenecarboxylate, bis(3,4-epoxy-
Examples include 6-methyl-cyclohexylmethyl)adipate. Among these, reaction products of polyhydric alcohols and epichlorohydrin, ie, polyglycidyl ether compounds of polyhydric alcohols, are particularly preferred because they exhibit excellent performance. Such polyepoxide compounds are usually used as emulsions. To make an emulsion or solution, for example, such a polyepoxide compound as it is or dissolved in a small amount of a solvent as necessary may be mixed with a known emulsifier such as sodium alkylbenzene sulfonate, dioctyl sulfosuccinate sodium salt, nonyl Emulsify or dissolve using a phenol ethylene oxide adduct. Next, the blocked polyisocyanate compound (D) used in the first treatment agent of the present invention is an addition compound of a polyisocyanate compound and a blocking agent,
The blocking component is liberated by heating to produce an active polyisocyanate compound. Examples of the polyisocyanate compound include tolylene diisocyanate, metaphenylene diisocyanate, diphenylmethane diisocyanate,
Polyisocyanates such as hexamethylene diisocyanate, polymethylene polyphenyl isocyanate, triphenylmethane triisocyanate,
Alternatively, these polyisocyanates and a compound having two or more active hydrogen atoms, such as trimethylolpropane, pentaerythritol, etc., are combined with an isocyanate group (-NCO) and a hydroxyl group (-
Examples include polyalkylene glycol adduct polyisocyanates containing terminal isocyanate groups obtained by reacting at a molar ratio of more than 1 with OH). In particular, aromatic polyisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate, and polymethylene polyphenyl isocyanate are preferred because they exhibit excellent performance. Examples of blocking agents include phenol,
Phenols such as thiophenol, cresol, and resorcinol, aromatic secondary amines such as diphenylamine and xylidine, phthalic acid imides,
Examples include lactams such as caprolactam and valerolactam, oximes such as acetoxime, methyl ethyl ketone oxime, and cyclohexane oxime, and acidic sodium sulfite. Rubber latex used in the first treatment agent of the present invention
Examples of (E) include natural rubber latex, styrene-butadiene copolymer latex, vinylpyridine-styrene-butadiene terpolymer latex, nitrile rubber latex, chloroprene rubber latex, etc., and these may be used alone or in combination. and use it. Among these, vinylpyridine-styrene-butadiene terpolymer latex shows excellent performance when used alone or when used in an amount of 1/2 or more. The first treatment agent is the above polyepoxide compound (C),
Contains a blocked polyisocyanate compound (D) and rubber latex (E), and the weight ratio of each component (C), (D), and (E) is (C)/[(C)+(D)] from 0.05 to 0.9, (E)/[(C)+
(D)] is preferably used in a range of 0.5 to 15. Especially (C)/[(C)+(D)] is 0.1 to 0.5, (E)/
It is preferable to blend them so that [(C)+(D)] is in the range of 1 to 10. If (C)/[(C)+(D)] is out of the above range, the rate of rubber adhesion to polyester fibers tends to be poor, and the adhesiveness tends to decrease.
If (E)/[(C)+(D)] is smaller than the above range, the treated polyester fiber will become hard and there is a risk of a decrease in fatigue resistance.On the other hand, if it is larger than the above range, adhesiveness will decrease. It's coming. The total solid concentration of the polyoxide compound (C), blocked polyisocyanate compound (D) and rubber latex (E) is 1 to 30 wt%, preferably 3 to 20 wt%, based on the weight of the fibers.
If the concentration is too low, the adhesion will decrease, and if the concentration is too high, it will become hard and the fatigue resistance will decrease. When the first treatment agent composition is used as an aqueous dispersion, the appropriate amount of the dispersant, that is, the surfactant, is preferably 0 to 15 wt% based on the total solid content of the first treatment agent.
The content is 10wt% or less, and if it exceeds the above range, the adhesiveness tends to decrease slightly. The second treatment agent of the present invention is a composition containing resorcinol/formalin/rubber latex, and the resorcinol/formalin rubber latex used here is usually called RFL, which has a molarity of resorcinol and formaldehyde. Ratio is 1:0.1
-1:8, preferably 1:0.5-1:5, more preferably 1:1-1:4. Examples of rubber latex include natural rubber latex, styrene-butadiene copolymer latex, vinylpyridine-styrene-butadiene terpolymer latex, nitrile rubber latex, chloroprene rubber latex, etc.
These can be used alone or in combination. Among these, vinylpyridine-styrene-butadiene terpolymer latex shows excellent performance when used alone or when used in an amount of 1/2 or more. The blending ratio of resorcin formalin and rubber latex depends on the addition ratio of the ethylene urea compound (F) and cresol novolac type epoxy compound (A) described below, but the solid content ratio is 1:1 to 1:15,
Preferably, the ratio is in the range of 1:3 to 1:12. If the proportion of rubber latex is too low, the treated polyester fiber material will become hard and its fatigue resistance will deteriorate. On the other hand, if the amount is too large, satisfactory adhesive strength and rubber adhesion rate cannot be obtained. The mixing ratio of ethylene urea compound (F) and cresol novolac type epoxy compound (A) is 40/60 to 80/
20 (weight ratio), and the mixture is added in an amount of 0.5 to 30 wt%, preferably 1.0 to 20 wt%, based on the above RFL. If the amount of the mixture added is too small, good adhesion and rubber adhesion cannot be obtained. On the other hand, if the amount added is too large, the viscosity of the processing agent will increase significantly, making it difficult to process the fiber material. Moreover, adhesive strength,
When the rubber adhesion rate reaches a saturation value, increasing the amount of the mixture added will not be effective and will only increase costs, and the treated fiber material will become significantly harder and less strong. Defects arise. The ethylene urea compound added to the second treatment agent is represented by the following general formula (F). [R is an aromatic or aliphatic hydrocarbon residue.
n is an integer of 0 to 2, and when n=0, the terminal group is hydrogen. ] Representative compounds include aromatic and aliphatic isocyanates such as octadecyl isocyanate, hexamethylene diisocyanate, isophorone diisocyanate, tolylene diisocyanate, metaxylene diisocyanate, diphenylmethane diisocyanate, naphthylene diisocyanate, triphenylmethane triisocyanate, and ethylene. Reaction products with imines are mentioned, and in particular aromatic ethylene urea compounds such as diphenylmethane diethylene urea give good results. In the present invention, the ethylene urea compound (F) and the cresol novolak type epoxy compound (G) have a catalytic effect on each other. , the epoxy ring opens and reacts to improve adhesion, while also increasing the cohesive force of the adhesive itself.As a result, it creates a strong chemical bond with the amines generated in the rubber, preventing adhesive deterioration. It is. Furthermore, due to the synergistic effect with the heat resistance of the nylon resin applied as the first treatment agent, adhesive deterioration is suppressed to a minimum, thereby exhibiting good heat-resistant adhesive properties. The above-mentioned second processing agent is usually adjusted to contain a solid content of 10 to 25% by weight. In order to attach the first treatment agent and the second treatment agent to the polyester fiber material, any method such as contact with a roller, application by spraying from a nozzle, or immersion in a solution can be adopted. The amount of solid content deposited on the polyester fiber is 0.1 to 10% by weight for the first treatment agent composition, preferably 0.5 to 5% by weight, and 0.5 for the second treatment agent composition.
It is suitable that the amount is 10 to 10% by weight, preferably 1 to 5% by weight. In order to control the amount of solid content attached to the fibers, means such as scraping off with a squeezing scraper using a pressure roller, blowing off with air, and beating with a suction heater may be used. In the present invention, after the polyester fiber is treated with the first treatment agent, the temperature is 50°C or more and 10°C or more lower than the melting point of the polyester fiber, preferably 220°C or more.
It is dried and heat-treated at a temperature of 260°C, then treated with a second treatment agent, and dried and heat-treated at a temperature of 120°C or higher and below the melting point of the polyester fiber, preferably 180-250°C. If the drying/heat treatment temperature is too low, adhesion with rubber will be insufficient, while if the temperature is too high, the polyester fibers will melt or fuse, or the strength will significantly decrease, making it impossible to put it to practical use. <Effects of the Invention> Compared to conventional methods, the fibers treated by the method of the present invention can be molded with rubber without impairing their moldability.
Improves heat-resistant adhesion, and improves durability in terms of peel strength and pull-out strength. <Example> Hereinafter, the present invention will be specifically described with reference to Examples. In the Examples, the heat resistance in rubber, cord peeling adhesive strength, T adhesive strength, and inter-ply peeling force were determined as follows. <Heat resistance in rubber> This indicates the strength retention rate after vulcanization in rubber. After vulcanization in rubber at 170°C for 3 hours, the cord was taken out from the rubber, the tensile strength at break was determined at a speed of 200 mm/min, and the retention rate was determined by comparing it with the initial strength. <Cord peeling adhesive strength> This indicates the adhesive strength between the treated cord and rubber. Five cords are buried near the surface layer of the rubber sheet,
The force required to peel 5 cords from the rubber sheet at a speed of 200 mm/min after vulcanization at 150° C. for 30 minutes under pressure is expressed in kg/5 cords. <T adhesive strength> This indicates the adhesive strength between the treated cord and rubber. The cord was embedded in a rubber block, cured under pressure at 150°C for 30 minutes, and then the cord was pulled out from the rubber block at a speed of 200 mm/min. The force required for pulling out was expressed in kg/cm. <Peeling force between plies> Indicates the adhesive force with the treated cord. After embedding 2 plies of treated cord in rubber as a cross ply (cord density: 27 cords/inch) at a 90 degree angle and vulcanizing at 150℃ for 30 minutes, both plies were peeled off at a tensile speed of 200 mm/min. The force required to do so is expressed in kg/inch. <Rubber adhesion rate> This is a measure of the adhesion of rubber to fibers.
During the above inter-ply peel force measurement, the cord peeled off from the rubber was observed with the naked eye, and on the cord surface,
The area to which rubber is attached is expressed as a percentage. Examples 1 to 6, Comparative Examples 1 to 7 Torezin FS-500 (manufactured by Teikoku Kagaku Sangyo Co., Ltd.; acrylamide graft compound of N-methoxymethylated nylon with a degree of methoxymethylation of 30%; graft ratio 25%) 20% solution 100g, ECN-1299 (Ciba・
8 g (manufactured by Geigy Co., Ltd.; epoxy compound of phenol-formalin resin condensate) was dissolved in toluene in advance, and 0.1 g of Neocol P (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.; dioctyl sulfosuccinate sodium salt) was dissolved in toluene.
Add and dissolve 0.6 g of methylcellulose to 28 g of water with stirring, add and mix the dispersed product, add this to 150 g of water with stirring and dissolve uniformly, and use it as a pretreatment agent. Denacol EX-611 (manufactured by Nagase Sangyo Co., Ltd.; sorbitol polyglycidyl ether) was added with Neocol SW-30 (Daiichi Kogyo Seiyaku Co., Ltd.) as a surfactant.
Add 4 g of 30% aqueous solution of dioctyl sulfosuccinate sodium salt (manufactured by Co., Ltd.) and dissolve uniformly. Add this to 805g of water while stirring, and add Denacol to 805g of water.
Uniformly dissolve EX-611 in water. Next, 14 g of Hiren MP (manufactured by DuPont; 4,4-diphenylmethane diisocyanate phenol block), 4 g of Neocol SW-30 and 42 g of water.
A dispersion obtained by mixing in a ball mill for 24 hours and 125 g of Nitzpol 2518GL (manufactured by Nippon Zeon Co., Ltd.; a 40% by weight water emulsion of vinylpyridine-styrene-butadiene terpolymer) were added and mixed uniformly. The obtained liquid mixture is used as a first treatment agent. In addition, 60 g of resorcinol formalin initial condensate (40% acetone solution) reacted with an acidic catalyst was added to the aqueous solution obtained by adding 10 g of 10% caustic soda aqueous solution and 30 g of 28% ammonia aqueous solution to 260 g of water and stirring well. and stir thoroughly to disperse. Next, 240g of Nitzpol 2518GL (manufactured by Nippon Zeon Co., Ltd., vinylpyridine-styrene-butadiene-terpolymer latex 40% water emulsion) and Nitzpol
100 g of L _x -112 (manufactured by Nippon Zeon Co., Ltd., 40% water emulsion of styrene-butadiene copolymer) is diluted with 200 g of water. Add the above resorcin-formalin initial condensate dispersion to this diluted solution while stirring slowly, and then add formalin (37% aqueous solution).
Add 20g and mix evenly. Next, add 14 g of diphenylmethane diethylene urea, 305 g of Neocol SW-30, and 36 g of water to this mixture in a ball mill.
Add and mix the aqueous dispersion obtained by stirring and mixing for 24 hours. Next, 7.2 g of ECN1299 (manufactured by Ciba Geigy Co., Ltd., an epoxy compound of phenol-formalin resin condensate) was dissolved in toluene in advance, and Neocol P (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., dioctyl sulfosuccinate sodium salt) was dissolved in toluene. ) 0.1g and methylcellulose 0.6g dissolved in 28g of water
The mixed solution obtained by adding and dispersing the mixture with stirring is used as a second treatment agent. [η] = 0.89 polyethylene terephthalate was melt-spun and stretched according to a conventional method to obtain a 1500 denier/
A multifilament of 192 filaments was obtained. Continue to apply the two multifilaments 40x.
The cord was twisted with 40T/10cm to obtain a 3000 denier/384 filament cord. These cords were immersed in the pretreatment agent using a Computer Treater processor (tire cord processor manufactured by CA Ritzler Co., Ltd.), and then dried and cured at 130° C. for 3 minutes. Pretreatment agent treatment can also be carried out at the time of yarn spinning. The amount of pretreatment agent deposited was 3.5wt%. Subsequently, after being immersed in the first treatment agent, the temperature was 150°C.
The sample was dried for 2 minutes at 230°C, and then heat treated at 230°C for 1 minute. Then, after being immersed in the second treatment agent, the temperature was 150°C.
for 2 minutes, followed by heat treatment at 230°C for 1 minute. The treated polyester tire cord includes a first
The solid content of the treatment agent was 2.2wt%, and the solid content of the second treatment agent was 2.5wt%. The treated cord thus obtained was embedded in unvulcanized rubber with a carcass composition mainly composed of natural rubber, and vulcanized at 150°C for 30 minutes (initial value) and at 170°C for 90 minutes (heat resistance value). As shown in Table 1 for the above experiment, the N of the pretreatment agent
- The weight ratio of the methoxymethylated nylon acrylamide graft compound (B) and the cresol novolak type epoxy compound (A) was variously changed, and the ethylene urea compound (F) of the second treatment agent and the cresol novolak type epoxy compound ( The weight ratio with A) was varied and repeated. The experimental results are shown in Table 1.

【table】

【table】

Claims (1)

[Claims] 1. A linear aromatic polyester fiber having the following general formula (A)
Treatment with a pretreatment agent containing a cresol novolak type epoxy compound represented by and aqueous nylon (B), followed by a first treatment containing a polyepoxide compound (C), a blocked polyiricyanate compound (D), and a rubber latex (E). treated with resorcinol, formalin, rubber latex (RFL)
A second compound in which an ethylene urea compound represented by the following general formula (F) and the above-mentioned cresol novolak type epoxy compound (A) were added in a weight ratio of (F)/(A) = 40/60 to 80/20. A method for treating polyester fibers, which comprises treating with a treatment agent. [Here, R' is -O-(CH ₂ ) _k -Cl, -O-(CH ₂ )- _l
OH or [O-(CH ₂ ) _n ] _n ′OH, R″ is H, CH ₃ ,
C ₂ H ₅ , K, l and m are integers of 1 to 4, m is an integer of 1 to 5, a and b are integers of 1 to 5, and a+b≦6. ] [Here, R is an aromatic or aliphatic hydrocarbon residue, and n is 0, 1 or 2. When n=0, the terminal group is hydrogen. ]