JPH0367146B2 - - Google Patents

Description

Detailed Description of the Invention <Field of Industrial Application> The present invention relates to a method for treating polyester fibers, and its purpose is to produce polyester fibers that have dramatically improved heat-resistant adhesion between the fibers and rubber. The purpose is to provide a processing method. In particular, the present invention relates to a novel treatment method for improving the adhesion performance between the reinforced polyester fiber and rubber and providing excellent fatigue resistance when the polyester fiber reinforced rubber composite is used under high load and high temperature conditions. It is. <Prior art> Polyester fibers, represented by polyethylene terephthalate fibers, have physical properties such as high strength and Young's modulus, low elongation and creep, and excellent fatigue resistance, and are used as composites for rubber reinforcement. It is used for general purposes such as the body. However, polyester fibers have poor adhesion to rubber materials compared to polyamide fibers such as nylon 6 and nylon 6/6, and ordinary adhesive treatment is not sufficient to fully demonstrate the physical properties of the polyester fibers. Strong adhesion 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 purpose, the surface of polyester fibers is coated with, for example, epoxy compounds,
A method of imparting adhesive properties by treatment with a highly reactive substance such as an isocyanate compound has been proposed (for example, Japanese Patent Publication No. 55632/1983, Japanese Patent Publication No. 47/1983).
49768, etc.). However, if an attempt is made to improve the adhesion of polyester fibers to rubber, problems arise in that the treated fiber material becomes hard and difficult to mold, and its fatigue resistance decreases. <Object of the invention> The present invention was made against the background of the above circumstances, and the purpose of the present invention is to provide excellent performance in adhesion between polyester fiber and rubber, particularly in heat-resistant adhesion. be. In order to achieve this object, the present invention has been devised as a treatment method for imparting adhesive properties, particularly excellent heat-resistant adhesive properties, between polyester fibers and rubbers. <Structure of the Invention> That is, the present invention comprises (1) treating a linear aromatic polyester fiber whose surface has been previously treated with a polyepoxide compound with a pretreatment agent containing a polyepoxide compound (A) and N-methoxymethyl nylon (B); Next, it is treated with a first treatment agent containing a polyepoxide compound (C), a blocked polyisocyanate compound (D), and a rubber latex (E), and then the resorcinol-formalin rubber latex (RFL) is treated with the following general formula.
A compound containing an ethylene urea compound represented by (F) and a cresol novolak type epoxy compound represented by the following general formula (G) in a weight ratio of (F)/(G) = 40/60 to 80/20. This is a method for treating polyester fibers, which is characterized by treating with two treatment agents. [Here, R is an aromatic or aliphatic hydrocarbon residue, and n is 0, 1 or 2. When n=0, the terminal group is hydrogen. ] [Here, R' is -O(-CH ₂ ) _-k Cl, -O(-CH ₂ )- _l O
H
or [-O( _-CH2 )-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. ] The polyepoxide compound used in the surface treatment of polyester fibers of the present invention and 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 contains ethylene glycol, glycerol, etc. , reaction products of polyhydric alcohols such as sorbitol, pentaerythritol, and polyethylene glycol and halogen-containing epoxides such as epichlorohydrin, resorcinol, bis(4-hydroxyphenyl)dimethylmethane, phenol formaldehyde resin, resorcinol formaldehyde resin reaction products of polyhydric phenols such as and the halogen-containing epoxides, polyepoxide compounds obtained by oxidizing unsaturated compounds with peracetic acid or hydrogen peroxide, i.e., 3,4-epoxycyclohexene epoxide, 3,4 -epoxycyclohexylmethyl-3,4-epoxycyclohexenecarboxylate, bis(3,4-epoxy-6-methyl-cyclohexylmethyl)adipate, and the like. 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, nonylphenol ethylene oxide. Emulsify or dissolve using adducts, etc. Next, the N-methoxymethyl nylon used in the pretreatment agent of the present invention is a nylon made from nylon resin and chemically modified by reacting formaldehyde and methanol to make it soluble in alcohol. It is obtained by replacing the hydrogen of -NHCO- with a methoxymethyl group -CH ₂ OCH ₃ and is represented by the following chemical formula. This may be further grafted with acrylic acid, acrylamide, or the like to add a carboxyl group to make it water-soluble. The above-mentioned polyepoxide compound is added to this, and the weight ratio of N-methoxymethyl nylon (B)/polyepoxide compound (A) is
(B)/(A) Blend at 100/10 to 100/80. Especially 100/
It is preferable to mix them in a ratio of 10 to 100/50 (weight ratio).
If (B)/(A) is out of the above range, the cohesive force or crosslinking density of the nylon coating will be insufficient, resulting in decreased adhesion or hardness, resulting in decreased fatigue resistance. The total solid content concentration including N-methoxymethyl nylon (B) and polyepoxide compound (A) is 1 to 30 wt%, preferably 3 to 20 wt% based on the weight of the fiber. 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. Next, the blocked polyisocyanate compound used in the first treatment agent of the present invention is an addition compound of a polyisocyanate compound and a blocking agent, and the blocking component is liberated by heating to produce an active polyisocyanate compound. be. Examples of the polyisocyanate compound include polyisocyanates such as tolylene diisocyanate, metaphenylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, polymethylene polyphenyl isocyanate, and triphenylmethane triisocyanate, or these polyisocyanates and active hydrogen atoms. A polyalkylene glycol containing terminal isocyanate groups obtained by reacting a compound having two or more such as trimethylolpropane, pentaerythritol, etc. at a molar ratio of isocyanate groups (-NCO) to hydroxyl groups (-OH) exceeding 1. Examples include adduct polyisocyanate.
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 phenols such as phenol, thiophenol, cresol, and resorcinol; aromatic secondary amines such as diphenylamine and xylidine; phthalic acid imides; lactams such as caprolactam and valerolactam;
Examples include oximes such as acetoxime, methyl ethyl ketone oxime, and cyclohexane oxime, and acidic sodium sulfite. Examples of the rubber latex used in the first treatment agent of the present invention 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 first treatment agent is the above polyepoxide compound (C),
Contains blocked polyisocyanate compound (D) and rubber latex (E), and the weight ratio of each component (C), (D), and (E) is (C)/[(C)+(D)] is 0.05 to 0.9 , (E)/[(C)+(D)
]
It is preferable to use 0.5 and 15. In particular, (C)/[(C)+(D)] is 0.1 to 0.5, (E)/[(C)+
(D)] is preferably 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 [(C)+(D)] is smaller than the above range, the treated polyester fibers will become hard, which may lead to a decrease in fatigue resistance, while if it is larger than the above range, adhesiveness will be reduced. The total solid content of the polyepoxide 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 using the first treatment agent composition as an aqueous dispersion, the appropriate amount of the dispersant, that is, the surfactant, is 0 to 15 wt%, preferably 0 to 15 wt%, based on the total solid content of the first treatment agent.
It 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, and rubber latex, and the resorcinol, formalin, and rubber latex used here is usually called RFL, and the molar ratio of resorcinol and formaldehyde is is 1:
It is used in a range of 0.1 to 1:8, preferably 1:0.5 to 1:5, more preferably 1:1 to 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 (G) 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 small, the treated polyester fiber material will become hard and have poor fatigue resistance. On the other hand, if there is too much adhesive strength,
Rubber adhesion rate cannot be obtained. The mixing ratio of ethylene urea compound (F) and cresol novolak type epoxy compound (G) 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 RFL. If the amount of the mixture added is too small, good adhesive strength and rubber adhesion rate cannot be obtained. On the other hand, if the amount added is too large, the viscosity of the processing agent increases significantly, making it difficult to process the fiber material. Moreover, adhesive strength,
When the rubber adhesion rate reaches a saturation value, the effect of increasing the amount of the mixture added is not increased, and the cost only increases, and the fiber material after treatment becomes extremely hard and loses its strength. 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. Similarly, the cresol novolac type epoxy compound added to the second treatment agent is represented by the following general formula (G). [Here, R' is -O-(CH ₂ ) _k Cl, -O-(CH ₂ ) _l -
OH or [-O( _-CH2 )-n _{] -n'OH} , R'' is -H, -
CH ₃ , -C ₂ H ₅ , k, l, m are 1
An integer of ~4, m' is an integer of 1 to 5, a, b are an integer of 1 to 5.
It is an integer of 5 and a+b≦6. ] Various compounds that satisfy the above (D) can be considered, but
Molecular weight 1200-1300, epoxy value 4.0-4.5eg/Kg
gives 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 adhesion with a roller, application by spraying from a nozzle, or immersion in a solution can be adopted. The solid content adhesion to polyester fibers is 0.1 to 10% by weight, preferably 0.5% by weight as the first treatment agent composition.
~5% by weight, 0.5~10 as the second treatment agent composition
It is preferable to apply it in an amount of 1 to 5% by weight, preferably 1 to 5% by weight. In order to control the solid content attached to the fibers, means such as squeezing with a pressure roller, scraping with a scraper, blowing off with air, suction, and beating with a beater are used. In the present invention, the polyester fibers are treated with the treatment agent and then cured at a temperature of 130°C or higher, and then treated with the first treatment agent at a temperature of 50°C or higher, preferably at least 10°C lower than the melting point of the polyester fiber. Drying and heat treatment at a temperature of 220 to 260°C, followed by treatment with a second treatment agent, to a temperature of 120°C or higher and below the melting point of the polyester fiber, preferably 180 to 250°C.
Dry and heat treat at a temperature of . 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 be significantly reduced, making it impossible to put it to practical use. <Effects of the Invention> Compared to conventional methods, fibers treated by the method of the present invention have improved heat-resistant adhesion and improved peel strength and durability without impairing moldability with rubber. <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 are values 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,
Vulcanize at 150°C for 30 minutes under pressure. Next, the force required to peel five cords from the rubber sheet at a speed of 200 mm/min was 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 and vulcanized under pressure at 150°C for 30 minutes, then the cord was pulled out from the rubber block at a speed of 200 mm/min, and the force required for pulling out was expressed in kg/cm. (Peeling force between plies) This indicates the adhesive force with the treated cord. After embedding two plies of treated cords in rubber as cross-plies (cord density: 27 cords/inch) at a 90 degree angle and vulcanizing them at 150℃ for 30 minutes, both plies were peeled off at a tensile speed of 200mm/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.
The cord peeled off from the rubber during the inter-ply peel force measurement described above was observed with the naked eye, and the portion of the cord surface to which the rubber was attached is expressed as a percentage. Examples 1 to 6, Comparative Examples 1 to 7 6 g of Deconal 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 Manufacturer, Inc., and dissolve uniformly. Add this to 805g of water while stirring, and
-611 is uniformly dissolved in water. Next, 1 g of piperazine as a reaction catalyst is added and mixed uniformly to form a surface treatment agent for fibers. Next, Torezin FS-500 (manufactured by Teikoku Kagaku Sangyo Co., Ltd.,
Acrylamide graft compound of N-methoxymethylated nylon) Add Denacol to 100g of 30% solution.
Add 5 g of EX-314 (manufactured by Nagase Sangyo Co., Ltd., glycerol polyglycidyl ether), and uniformly dissolve and mix. Add this to 150 g of water while stirring and dissolve uniformly to obtain a pretreatment agent. Denacol EX-611 6g and Neocol SW-30 (Daiichi Kogyo Seiyaku Co., Ltd., 30% dioctyl sulfosuccinate sodium salt) as a surfactant.
Add 4g of aqueous solution and dissolve uniformly. water this
Add Denacol EX- to 805g while stirring.
Dissolve 611 uniformly in water. Next, Hiren
MP (manufactured by DuPont, 4,4-diphenylmethane diisocyanate phenol block)
A dispersion obtained by mixing 14 g of Neocol SW-30, 4 g of Neocol SW-30, and 42 g of water in a ball mill for 24 hours, and Nitupol 2518GL (manufactured by Nippon Zeon Co., Ltd., a 40% water emulsion of vinylpyridine-styrene-butadiene terpolymer) ) Add 125g and mix evenly. The obtained liquid mixture is used as a first treatment agent. In addition, 10 g of a 10% caustic soda aqueous solution and 30 g of a 28% ammonia aqueous solution were added to 260 g of water, and stirred well. Into the resulting aqueous solution, 60 g of a resorcinol-formalin initial condensate (40% acetone solution) reacted with an acidic catalyst was added. Add 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
100g of LX-112 (manufactured by Nippon Zeon Co., Ltd., 40% water emulsion of styrene-butadiene copolymer) and 200g of water.
Dilute with In this diluted solution, the above resorcinol.
Add formalin initial condensation dispersion while stirring slowly, and then add formalin (37% aqueous solution).
Add 20g and mix evenly. Next, an aqueous dispersion obtained by stirring and mixing 14 g of diphenylmethane diethylene urea, 5 g of Neogol SW-30, and 36 g of water in a ball mill for 24 hours is added to this mixed solution and mixed. Next, ECN1299 (manufactured by Ciba Geigy Co., Ltd.,
Dissolve 7.2 g (epoxy compound of phenol formalin resin condensate) in toluene in advance, add 0.1 g Neocol P (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., dioctyl sulfosacnate sodium salt) and 0.6 g methylcellulose, and dissolve. The dispersion was added to 28 g of water that had been prepared while stirring and mixed, and the resulting liquid mixture was used as the second treatment agent. Polyethylene terephthalate with [η] = 0.89 was melt-spun and stretched according to a conventional method to obtain 1500 denier/
A multifilament of 192 filaments was obtained.
During spinning, a surface treatment agent having the composition shown above was applied. Continue to apply the two multifilaments 40x.
A 3000 denier/384 filament cord was obtained by twisting 40T/10cm. These cords were immersed in the above pretreatment agent using a computer treater processor (tire cord processor manufactured by CA Ritzler Co., Ltd.), dried at 130°C for 3 minutes, and then soaked in the first treatment agent. After immersion, it is dried at 150°C for 2 minutes and then heat treated at 230°C for 1 minute. Then, after immersing in the second treatment agent,
Dry at 150°C for 2 minutes, followed by heat treatment at 230°C for 1 minute. The treated polyester tire cord had a solid content of 2.2 wt% of the first treatment agent and a solid content of 2.5 wt% of the second treatment agent. The treated code thus obtained is embedded in unvulcanized rubber compounded with a carcass whose main component is natural rubber.
Vulcanization was performed 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 polyepoxy compound (A) was variously changed, and the ethylene urea compound (C) and the cresol novolak type epoxy compound (D) of the second treatment agent were The experiment was repeated with various weight ratios. The experimental results are shown in Table 1. 【table】

Claims (1)

[Claims] 1. Linear aromatic polyester fibers whose surface has been previously treated with a polyepoxide compound are mixed with a polyepoxide compound (A) and N-methoxymethyl nylon.
(B) is treated with a pretreatment agent containing a polyepoxide compound (C) a blocked polyisocyanate compound.
(D) and rubber latex (E), and then an ethylene urea compound represented by the following general formula (F) and the following general formula (G) are added to resorcin, formalin, and rubber latex (RFL). The cresol novolak type epoxy compound represented by (F)/
(G) A method for treating polyester fibers, comprising treating with a second treating agent containing a weight ratio of 40/60 to 80/20. [Here, R is an aromatic or aliphatic hydrocarbon residue, and n is 0, 1 or 2. When n=0, the terminal group is hydrogen. ] [Here, R' is -O(-CH ₂ ) _-k Cl, -O(-CH ₂ )- _l O
H
or [-O( _-CH2 )-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. ]