Auxiliary crosslinker emulsion for latex vulcanization as well as preparation method and application of auxiliary crosslinker emulsion

Abstract

The invention provides an assistant crosslinker emulsion for latex vulcanization. The assistant crosslinker emulsion at least comprises the following components in percentage by weight: 20-50% of assistant crosslinker; 0.5%-15% of an emulsifier; 5%-30% of a solvent; 1%-10% of an anti-freezing agent; 0.1%-2% of an auxiliary agent; 23%-48.4% of water; the invention also provides a preparation method of the assistant crosslinker emulsion for latex vulcanization. The assistant crosslinker for latex vulcanization prepared by the invention is small in emulsion particle size, good in stability and long in storage time, is matched with an organic peroxide emulsion for use, is small in addition amount, obviously improves the crosslinking degree and the crosslinking depth, eliminates peculiar smell generated after crosslinking of some peroxides such as DCP (dicumyl peroxide), improves the quality of a product and improves the performance of the product.

Description

Technical Field

[0001] The invention relates to the technical field of latex vulcanization, in particular to a co-crosslinking agent emulsion for latex vulcanization and a preparation method and application thereof. Background Art

[0002] Organic peroxide vulcanization system is one of the important methods of rubber vulcanization; organic peroxide vulcanization system refers to a formula system for vulcanizing rubber by using peroxide compounds as oxidants, together with vulcanizing agents, control agents and additives. Compared with traditional vulcanization systems, organic peroxide vulcanization systems have fast vulcanization speed, low vulcanization temperature, high vulcanization efficiency, and significantly improved physical properties and thermal oxidation aging properties of vulcanized products. However, compared with sulfur vulcanization, the wear resistance and dynamic properties of peroxide vulcanized rubber alone are relatively poor. Adding certain multifunctional monomers (cross-linking agents) with free radical polymerization properties to the peroxide vulcanization system can overcome these shortcomings to a certain extent, while improving the cross-linking efficiency of peroxides, accelerating the vulcanization speed, reducing the decomposition rate of peroxides, and maintaining the excellent properties of vulcanized rubber. Certain cross-linking agents can also effectively reduce the odor of vulcanized rubber. For example: Guo Shenrong, Wang Mingchao, Lu Guolin, etc. "The influence of cross-linking agents on the vulcanization performance of EPDM peroxide vulcanization system" was studied in order to improve the performance of ethylene propylene diene monomer (EPDM) rubber by changing the vulcanization system. The effects of triallyl isocyanurate (TAIC), N,N′-phenylene bismaleimide (PDM) and sulfur (S) cross-linking agents on EPDM rubber in peroxide bis(tert-butylperchlorinated)trimethylcyclohexane (TMCH) system and diisopropylbenzene perchloride (DCP) system were studied respectively. The cross-linking density, mechanical tensile properties and vulcanization characteristic curves of the sample films were investigated, and the vulcanization differences and vulcanization characteristics among the cross-linking agents were analyzed. The influence of each cross-linking agent on the vulcanization performance of the peroxide system was clarified through experimental analysis. The results showed that with the increase of TAIC dosage, the tensile strength of the DCP system increased by 220%.

[0003] Li Xiuming, Zou Hua, Liu Jun, etc., in the article "Optimization of the crosslinking agent combination in the sulfur / peroxide vulcanization system of natural rubber", used the orthogonal test method to study the optimization of the crosslinking agent ZDMA, HVA-2, TAIC and BDDA in the sulfur / peroxide vulcanization system of natural rubber. The results show that ZDMA, HVA-2 and TAIC have a highly significant effect on the elongation at break of the rubber compound, ZDMA, HVA-2 and TAIC have a significant effect on the tear strength and tensile fatigue properties of the rubber compound, BDDA has a certain effect on the elongation at break, tear strength and tensile fatigue properties of the rubber compound, ZDMA has a significant effect on the thermal aging properties of the rubber compound, and HVA-2, TAIC and BDDA have a certain effect on the thermal aging properties of the rubber compound.

[0004] Zhang Peiting, Gao Hongqiang, Xiao Jianbin, et al., studied the application of crosslinking agents in hydrogenated nitrile rubber. They studied the vulcanization characteristics and physical properties of hydrogenated nitrile rubber (HNBR) with different amounts of crosslinking agents, oligomeric esters and trimethylolpropane trimethacrylate (TMPTMA), and compared the effects of the two crosslinking agents on the vulcanization characteristics, physical properties, aging properties, high-temperature tensile properties, wear resistance and processing properties of HNBR. The results show that with the increase of the amount of oligomeric esters or TMPTMA, the torque of HNBR rubber increases, the vulcanization time shortens, the tensile strength remains basically unchanged, the hardness, 100% tensile stress and tear strength gradually increase, and the elongation at break and rebound value decrease. Compared with the rubber with oligomeric esters, the rubber with TMPTMA has a larger torque and a shorter vulcanization time; compared with the rubber with oligomeric esters and TMPTMA, the physical properties, aging properties, high-temperature tensile properties and wear resistance are very close, that is, the working principles of the two are similar. The rubber with TMPTMA has a smaller storage modulus and a larger loss factor.

[0005] The latex compounding method is fundamentally different from that of raw rubber. Latex is a water dispersion system with good fluidity. The mechanical force required to disperse the compounding agent in latex is much smaller than that in the tough raw rubber. Therefore, the equipment used for latex compounding is lightweight equipment. In addition, since most of the compounding agents are solid powders and liquids that are insoluble in water, they must be processed in advance before being added to latex. For example, solid powder compounding agents must first be prepared into a water dispersion by wet dispersion and crushing, and liquid compounding agents that are insoluble in water must also be prepared into an emulsion.

[0006] The peroxide emulsions disclosed in patents CN1335859A, CN115702171 A, etc., all of which are peroxide esters; the peroxides in the peroxide emulsions disclosed in patents CN115667319A, CN108779070A are peroxide esters and diacyl peroxides; the above peroxide emulsions are used as polymerization initiators for synthesizing ethylenically unsaturated monomers of various types of polymers, and are used alone; while organic peroxide emulsions such as alkyl peroxides: diisopropyl peroxide DCP, cumene hydroperoxide CHP, di(tert-butylperoxide isopropyl)benzene) BIPB used for latex vulcanization have not been reported, and crosslinking aid emulsions suitable for use with the above alkyl peroxides have not been reported. Summary of the invention

[0007] In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a cross-linking agent emulsion for latex vulcanization and its preparation method and application, so as to obtain a cross-linking agent emulsion that can be used in combination with alkyl peroxide to promote latex vulcanization.

[0008] To achieve the above object and other related objects, the present invention provides a co-crosslinking agent emulsion for latex vulcanization, comprising at least the following components in weight proportion:

[0009]

[0010] The present invention also provides a method for preparing the above-mentioned auxiliary cross-linking agent emulsion for latex vulcanization, comprising the following steps:

[0011] 1) adding a cross-linking agent, an emulsifier, a solvent, an antifreeze agent and some auxiliary agents into water according to the formula amount to obtain a mixed solution;

[0012] 2) heating the mixed solution, stirring the mixture for reaction, homogenizing and emulsifying to obtain an emulsion;

[0013] 3) Cooling the emulsion, adding the remaining auxiliary agent and water during the cooling process until the temperature reaches room temperature, to obtain a cross-linking agent emulsion.

[0014] The present invention also provides an application of the above-mentioned latex vulcanization auxiliary cross-linking agent emulsion in latex vulcanization, wherein the latex vulcanization auxiliary cross-linking agent emulsion is used in combination with an organic peroxide emulsion to vulcanize the latex, and the weight ratio of the latex vulcanization auxiliary cross-linking agent emulsion to the organic peroxide emulsion is: 20-25:10-15.

[0015] As described above, the cross-linking agent emulsion for latex vulcanization and the preparation method thereof of the present invention have the following beneficial effects:

[0016] The cross-linking aid emulsion for latex vulcanization of the present invention is prepared by using a cross-linking aid, an emulsifier, a solvent, an antifreeze agent, an auxiliary aid and water, and has small emulsion particle size, good stability and long storage time; it is used in combination with an organic peroxide emulsion, has a small addition amount, and significantly improves the cross-linking degree and the depth of cross-linking; it eliminates the peculiar smell generated by some peroxides such as DCP after cross-linking, improves the quality of the product, and improves the performance of the product.

[0017] The auxiliary cross-linking agent emulsion for latex vulcanization of the present invention uses water as a main dispersion body, broadens the application scenarios of the auxiliary cross-linking agent, and is suitable for the production vulcanization process of latex. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It shows the auxiliary cross-linking agent emulsion for latex vulcanization prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0019] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0020] Please refer to the attached drawings. It should be noted that the illustrations provided in this embodiment are only used to illustrate the basic concept of the present invention in a schematic manner, and the drawings only show the components related to the present invention rather than the number, shape and size of the components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0021] The first aspect of the present invention provides a co-crosslinking agent emulsion for latex vulcanization, comprising at least the following components in weight proportion:

[0022]

[0023]

[0024] In the auxiliary cross-linking agent emulsion for latex vulcanization of the present invention, the auxiliary cross-linking agent is selected from one or more of trimethylolpropane triacrylate (TMPTA), trimethylolpropane trimethacrylate (TMPTMA), ethylene glycol diacrylate (EGDA), ethylene glycol dimethacrylate (EGDMA), N,N′-p-phenylbismaleimide (PDM or HVA-2), zinc diacrylate (ZDA), zinc dimethacrylate (ZDMA), triallyl cyanurate (TAC), triallyl isocyanurate (TAIC), and 1,2-polybutadiene (1,2-PBR).

[0025] The higher the functionality of the auxiliary crosslinking agent, the more active groups it has, the denser the network structure formed further, and the higher the degree of crosslinking, so the auxiliary crosslinking agent in the present invention is preferably trifunctional. In a preferred embodiment of the present invention, the auxiliary crosslinking agent is selected from one or more of trimethylolpropane triacrylate (TMPTA), trimethylolpropane trimethacrylate (TMPTMA), and triallyl isocyanurate (TAIC).

[0026] In the latex vulcanization auxiliary cross-linking agent emulsion of the present invention, the emulsifier is selected from one or more of anionic emulsifiers, cationic emulsifiers, nonionic emulsifiers, and polymer emulsifiers. In a preferred embodiment of the present invention, the emulsifier is selected from nonionic emulsifiers and polymer emulsifiers.

[0027] The nonionic emulsifier is selected from emulsifiers with an HLB value greater than 8 and no APEO, such as condensates of fatty acids and ethylene oxide, fatty ethylene fatty acid esters, condensates of castor oil / hydrogenated castor oil and ethylene oxide, polyoxyethylene sorbate, fatty alcohol polyoxyethylene ethers, and polyoxyethylene / polyoxypropylene block polymers.

[0028] The polymer emulsifier is selected from polyvinyl alcohol or hydrolyzed polyvinyl acetate.

[0029] In the auxiliary cross-linking agent emulsion for latex vulcanization of the present invention, the solvent is selected from one or more of isododecane, odorless petroleum solvent oil (OMS), petroleum solvent oil type aliphatic, aliphatic dibasic acid esters, phthalates, polybenzoic acid esters, benzoates, polyol esters, chlorinated hydrocarbons, epoxies, citrates, and polyesters.

[0030] Wherein, the petroleum solvent oil type aliphatic is selected from one or more of commercially available solvent oils such as 70#, 90#, 120#, 180#, 190#, 200#, etc.

[0031] The aliphatic dibasic acid ester is selected from one or more of di(2-ethylhexyl) adipate (DOA), di(2-ethylhexyl) sebacate (DOS) or di(2-ethylhexyl) azelaic acid (DOZ).

[0032] The phthalates are selected from one or more of di(2-ethylhexyl) phthalate (DEHP) and dibutyl phthalate (DBP).

[0033] The polybenzoic acid esters are selected from one or more of tri(2-ethylhexyl) trimellitate (TOTM), tri(2-isooctyl) trimellitate (TIOTM) or tri(2-isodecyl) trimellitate (TIDTM).

[0034] The benzoic acid esters are selected from one or more of diethylene glycol dibenzoate (DEDB), dipropylene glycol dibenzoate (DPGDB), triethylene glycol dibenzoate (TEDB), and 2,2,4-trimethyl-1,3-pentanediol-isobutyric acid-benzoate.

[0035] The polyol esters are selected from one or more of polyol fatty acid esters, polyol benzoates, glycerol fatty acid esters, pentaerythritol esters, and polyol phthalates.

[0036] The chlorinated hydrocarbons are selected from one or more of dichloromethane, trichloroethylene and carbon tetrachloride.

[0037] The epoxy is selected from one or more of acetone, toluene, xylene, butyl acetate, methanol and the like.

[0038] The citrate esters are selected from one or more of tributyl citrate (TBC) and acetyl tributyl citrate (ATBC).

[0039] The polyester is selected from one or more of tricresyl phosphate (TCP) and trioctyl phosphate (TOP).

[0040] Phthalate esters include phthalate esters (such as di(2-ethylhexyl)phthalate (DEHP) or dibutylphthalate (DBP)), terephthalate esters (such as di(2-ethylhexyl)phthalate (DOTP)).

[0041] In a preferred embodiment of the present invention, the solvent is selected from one or more of isododecane, odorless petroleum solvent spirit (OMS), and phthalates.

[0042] In the cross-linking agent emulsion for latex vulcanization of the present invention, the antifreeze agent is selected from one or more of ethylene glycol, 2-propanol, 1-propanol, propane-1,2-diol, propane-1,3-diol, glycerol, butane-1-ol, butane-2-ol, butane-1,3-diol, butane-1,4-diol, diethylene glycol, and triethylene glycol. In a preferred embodiment of the present invention, the antifreeze agent is selected from one or more of ethylene glycol, propylene glycol, and glycerol that have no effect on the stability of the latex.

[0043] In the auxiliary cross-linking agent emulsion for latex vulcanization of the present invention, the auxiliary auxiliary agent is selected from one or more of a pH regulator, a thickener and a preservative.

[0044] Wherein, the pH adjusting agent is selected from inorganic bases or organic amines. The organic amine is selected from one or more of aliphatic amines, alcohol amines, amides, alicyclic amines, aromatic amines, naphthyl amines, other amines, etc., and specifically can be one or more of monoethylamine, diethylamine, triethylamine, ethylenediamine, monoethanolamine, diethanolamine, triethanolamine multifunctional amine auxiliary agent AMP-95, etc. The inorganic base can be sodium hydroxide, potassium hydroxide, ammonia water, etc.

[0045] The thickener is selected from one or more of cellulose, bentonite and xanthan gum.

[0046] The cellulose is selected from one or more of methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose and hydroxypropyl methyl cellulose, and specific brands include commercially available HBR250, HHBR250, CMC and the like.

[0047] The bentonite is selected from one or more of bentonite, attapulgite, and aluminum silicate, and specific brands include commercially available SMJ-N, SMP-C, SMP, SMF-LV, and BP188.

[0048] The xanthan gum is selected from one or more of guar gum, carrageenan and xanthan gum.

[0049] The preservative is selected from one or more of formaldehyde, chloromethylisothiazolinone (CMIT), benzisothiazolinone (BIT), and methylisothiazolinone (MIT).

[0050] Among them, MITs include the commercially available Suzhou KEMES SKYBIO CM, SKYBIO BMF, SKYBIO SF10 / SF10Plus, etc.

[0051] BITs include SKYBIO B900, SKYBIO B20, SKYBIO B10, etc., which are commercially available from Suzhou Kemei.

[0052] The second aspect of the present invention provides a method for preparing the above-mentioned latex vulcanization auxiliary cross-linking agent emulsion, comprising the following steps:

[0053] 1) adding the cross-linking agent, emulsifier, solvent, antifreeze agent and the first part of auxiliary additives according to the formula amount to the first part of water to obtain a mixed solution;

[0054] 2) heating the mixed solution, stirring the mixture for reaction, homogenizing and emulsifying to obtain an emulsion;

[0055] 3) Cooling the emulsion, adding the second part of the auxiliary agent and the second part of water during the cooling process until the temperature drops to room temperature, to obtain a cross-linking agent emulsion.

[0056] Wherein, in step 2), the heating is water bath heating.

[0057] In step 2), the heating temperature is 30-70°C. For example, 30-35°C, 35-40°C, 40-45°C, 45-50°C, 50-55°C, 55-60°C, 60-65°C or 65-70°C. Heating the mixed solution can melt the solid components in the mixed solution. The temperature is selected according to the cloud point of the selected emulsifier, which is generally lower than the cloud point of the emulsifier. In a preferred embodiment of the present invention, the heating temperature is 40-60°C.

[0058] In step 2), the time of the stirring reaction is 10 to 30 minutes. For example, 10 to 15 minutes, 15 to 20 minutes, 20 to 25 minutes or 25 to 30 minutes. In a preferred embodiment of the present invention, the time of the stirring reaction is 15 to 25 minutes. The stirring rate of the stirring reaction is <1000r / min. For example, ≤400r / min, 400 to 500r / min, 500 to 600r / min, 600 to 700r / min, 700 to 800r / min, 800 to 900r / min or 900 to 1000r / min. Too fast a stirring rate will bring in more bubbles, and the emulsion is easy to form a three-phase stable system, affecting the stability of the emulsion. In a preferred embodiment of the present invention, the stirring rate of the stirring reaction is <700r / min.

[0059] In step 2), the homogenization is carried out in a homogenizer with a rotation speed of 7000-15000 r / min. The rotation speed of the homogenizer can be 7000-8000 r / min, 8000-9000 r / min, 9000-10000 r / min, 10000-11000 r / min, 11000-12000 r / min, 12000-13000 r / min, 13000-14000 r / min or 14000-15000 r / min. In a preferred embodiment of the present invention, the rotation speed of the homogenizer is 10000-13000 r / min.

[0060] In step 2), the emulsification time is 5 to 60 min. For example, 5 to 10 min, 10 to 15 min, 15 to 20 min, 20 to 25 min, 25 to 30 min, 30 to 35 min, 35 to 40 min, 40 to 45 min, 45 to 50 min, 50 to 55 min or 55 to 60 min. In a preferred embodiment of the present invention, the emulsification time is 15-30 min.

[0061] In step 3), the cooling is cooling under stirring, and the stirring rate is less than 1000 r / min. For example, it is ≤400 r / min, 400-500 r / min, 500-600 r / min, 600-700 r / min, 700-800 r / min, 800-900 r / min or 900-1000 r / min. In a preferred embodiment of the present invention, the stirring rate is less than 500 r / min.

[0062] In step 1) and step 3), the weight ratio of the first part of the auxiliary agent to the second part of the auxiliary agent is (0-2.5):(0-3), (0-0.5):(0-3), (0.5-1):(0-3), (1-1.5):(0-3), (1.5-2):(0-3), (2-2.5):(0-3), (0-2.5):(0-1), (0-2.5):(1-1.5), (0-2.5):(1.5-2), (0-2.5):(2-2.5) or (0-2.5):(2.5-3), and the first part of the auxiliary agent and the second part of the auxiliary agent are not both 0.

[0063] In step 1), the first part of the auxiliary agent is selected from a pH regulator. It is selected from an inorganic base or an organic amine. The organic amine is selected from one or more of aliphatic amines, alcohol amines, amides, alicyclic amines, aromatic amines, naphthyl amines, other amines, etc., and can be one or more of monoethylamine, diethylamine, triethylamine, ethylenediamine, monoethanolamine, diethanolamine, triethanolamine multifunctional amine auxiliary agent AMP-95, etc. The inorganic base can be sodium hydroxide, potassium hydroxide, ammonia water, etc.

[0064] In step 3), the second part of the auxiliary agent is selected from one or more of thickeners and preservatives. The thickener is selected from one or more of cellulose, bentonite, and xanthan gum; the cellulose is selected from one or more of methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, and hydroxypropyl methyl cellulose, and the specific brands are commercially available HBR250, HHBR250, CMC, etc. The bentonite is selected from one or more of bentonite, attapulgite, and aluminum silicate, and the specific brands are commercially available SMJ-N, SMP-C, SMP, SMF-LV, BP188; the xanthan gum is selected from one or more of guar gum, carrageenan, and xanthan gum. The preservative is selected from one or more of formaldehyde, chloromethylisothiazolinone (CMIT), benzisothiazolinone (BIT), and methylisothiazolinone (MIT).

[0065] In step 1) and step 3), the weight ratio of the first part of water to the second part of water is (50-175):(35-50). For example, (50-60):(35-50), (60-70):(35-50), (70-80):(35-50), (80-90):(35-50), (90-100):(35-50), (100-110):(35-50), (110-120):(35-50), (120-130):(35-50), ( 130~140):(35~50), (140~150):(35~50), (150~160):(35~50), (160~170):(35~50), (170~175):(35~50), (50~175):(35~40), (50~175):(40~45) or (50~175):(45~50).

[0066] The third aspect of the present invention provides an application of the above-mentioned cross-linking agent emulsion for latex vulcanization in latex vulcanization, wherein the cross-linking agent emulsion for latex vulcanization is used in combination with an organic peroxide emulsion to vulcanize the latex, and the weight ratio of the cross-linking agent emulsion for latex vulcanization to the organic peroxide emulsion is: 20-25:10-15.

[0067] Example 1

[0068] Preparation of cross-linking agent emulsion for latex vulcanization

[0069] 1) Weigh 210 g of TMPTMA, 9 g of emulsifier 1 (fatty alcohol polyoxyethylene ether) (HLB value 11-12), 280 g of emulsifier 2 (polymer emulsifier, PVA0588, solid content 15%), 65 g of solvent 23D-30 (aliphatic dibasic acid ester), 21 g of propylene glycol, 2 g of monoethanolamine, and 73 g of water, place in a beaker, heat in a water bath at 50° C., and stir at a speed of 500 r / min for 15 min to obtain a mixed solution;

[0070] 2) homogenizing and emulsifying the mixed solution with a homogenizer, the speed of the homogenizer is 13000r / min, and the emulsification time is 15min; obtaining an emulsion;

[0071] 3) stirring the emulsion to cool down, the stirring rate is 400r / min, adding 40g of water during the cooling process, and after cooling down to room temperature, the auxiliary crosslinking agent emulsion is obtained, which can be canned; the obtained auxiliary crosslinking agent emulsion for latex vulcanization is as shown in the attached Figure 1 shown.

[0072] Example 2

[0073] Preparation of cross-linking agent emulsion for latex vulcanization

[0074] 1) Weigh 210 g of TMPTMA, 56 g of emulsifier 3 (castor oil / hydrogenated castor oil and ethylene oxide condensate) (HLB value 13-14), 150 g of solvent 23D-30 (aliphatic dibasic acid ester), 30 g of propylene glycol, and 174 g of water, place them in a beaker, heat them in a water bath at 60° C., and stir them at a speed of 500 r / min for 10 min to obtain a mixed solution;

[0075] 2) homogenizing and emulsifying the mixed solution with a homogenizer, the speed of the homogenizer is 12000r / min, and the emulsification time is 10min; obtaining an emulsion;

[0076] 3) Stir the emulsion to cool down at a stirring rate of 450 r / min. During the cooling process, add 70 g of xanthan gum dispersion with a reinforcement content of 1%, 2.1 g of preservative BM (commercially available, containing benzisothiazolinone BIT and methylisothiazolinone MIT), and 7.9 g of water. After cooling to room temperature, the cross-linking agent emulsion is obtained and canned.

[0077] Example 3

[0078] Preparation of cross-linking agent emulsion for latex vulcanization

[0079] 1) Weigh 210 g of TMPTMA, 56 g of emulsifier 4 (castor oil / hydrogenated castor oil and ethylene oxide condensate) (HLB value 11.5-12.5), 187 g of emulsifier 2 (PVA0588, solid content 15%), 120 g of solvent 23D-30 (aliphatic dibasic acid ester), 21 g of propylene glycol, 1.5 g of monoethanolamine, and 56 g of water, place in a beaker, heat in a water bath at 40° C., and stir at a speed of 500 r / min for 20 min to obtain a mixed solution;

[0080] 2) homogenizing and emulsifying the mixed solution with a homogenizer, the speed of the homogenizer is 12500r / min, and the emulsification time is 10min; obtaining an emulsion;

[0081] 3) The emulsion is stirred and cooled at a stirring rate of 450 r / min. During the cooling process, 2.8 g of Defros D29 (commercially available, containing chloromethylisothiazolinone (CMIT), methylisothiazolinone (MIT) and formaldehyde) and 45.7 g of water are added. After cooling to room temperature, the cross-linking agent emulsion is obtained and canned.

[0082] Example 4

[0083] Preparation of cross-linking agent emulsion for latex vulcanization

[0084] 1) Weigh 105 g of TAIC, 105 g of TMPTA, 10.5 g of emulsifier 1 (fatty alcohol polyoxyethylene ether) (HLB value 11-12), 280 g of emulsifier 2 (PVA0588, solid content 15%), 80.5 g of solvent 23D-31 (terephthalate), 21 g of propylene glycol, 1.0 g of multifunctional amine auxiliary agent AMP-95, and 57 g of water, place them in a beaker, heat them in a water bath at 60° C., and stir them at a speed of 500 r / min for 20 min to obtain a mixed solution;

[0085] 2) homogenizing and emulsifying the mixed liquid with a homogenizer, the speed of the homogenizer is 12500r / min, and the emulsification time is 20min; obtaining an emulsion;

[0086] 3) The emulsion is stirred and cooled at a stirring rate of 450 r / min. During the cooling process, 2.8 g of Defros D29 (commercially available, containing chloromethylisothiazolinone (CMIT), methylisothiazolinone (MIT) and formaldehyde) and 37.2 g of water are added. After cooling to room temperature, the co-crosslinking agent emulsion is obtained and canned.

[0087] Example 5

[0088] Preparation of cross-linking agent emulsion for latex vulcanization

[0089] 1) Weigh 210 g of TAIC, 280 g of emulsifier 2 (PVA0588, solid content 15%), 96 g of solvent 23D-31 (terephthalate), 21 g of propylene glycol, 1.0 g of multifunctional amine auxiliary AMP-95, and 52 g of water, place them in a beaker, heat them in a water bath at 40° C., and stir them at a speed of 500 r / min for 20 min to obtain a mixed solution;

[0090] 2) homogenizing and emulsifying the mixed solution with a homogenizer, the speed of the homogenizer is 12500r / min, and the emulsification time is 30min; obtaining an emulsion;

[0091] 3) The emulsion is stirred and cooled at a stirring rate of 450 r / min. During the cooling process, 2.1 g of Defros D29 (commercially available, containing chloromethylisothiazolinone (CMIT), methylisothiazolinone (MIT) and formaldehyde) and 37.9 g of water are added. After cooling to room temperature, the cross-linking agent emulsion is obtained and canned.

[0092] Performance Testing

[0093] The performance of the latex vulcanization crosslinking agent emulsions prepared in Examples 1 to 5 was tested. The viscosity was tested using a Stormer STM-V viscometer, the pH was tested using a pH meter, and the particle size was tested using a BT-2600 laser particle size analyzer. The results are shown in Table 1.

[0094] Table 1 Performance of cross-linking agent emulsion for latex vulcanization

[0095]

[0096]

[0097] It can be seen from Table 1 that the latex vulcanization auxiliary crosslinking agent emulsion prepared by the present invention has a small particle size and good emulsion stability. Among them, no polymer emulsifier is used in Example 2. Since the polymer emulsifier has a large molecular weight and a thickening effect, the viscosity of the latex vulcanization auxiliary crosslinking agent emulsion in Examples 1, 3, 4, and 5 is larger, and the particle size after emulsification will be smaller. The latex vulcanization auxiliary crosslinking agent emulsion in Example 2 has a small viscosity and a larger particle size. The raw material TAIC in Example 5 has a larger specific gravity of 1.15g / cm 3 , while the specific gravity of the same volume of water is 1g / / cm 3 Its specific gravity is much greater than that of water, so there will be oil and water separation when it is left standing.

[0098] The latex vulcanization auxiliary crosslinking agent emulsion prepared in the above Examples 1 to 5 is compounded with a peroxide emulsion and other auxiliary agents to pre-vulcanize the latex. The vulcanization formula is shown in Table 2:

[0099] Table 2 Latex pre-vulcanization ingredients

[0100] raw material Example 6 Example 7 Example 8 Example 9 Example 10 Embodiment 11 Nitrile latex 900 900 900 900 Natural latex / / / / 900 900 DCP Emulsion 12.83 12.83 12.83 12.83 12.83 12.83 Example 1 / 22.44 / / / / Example 2 / / 22.44 / / / Example 3 / / / 22.44 / / Example 4 / / / / 22.44 / Example 5 / / / / / 22.44 Zinc Oxide 9.504 9.504 9.504 9.504 9.504 9.504 water 1800 1800 1800 1800 1800 1800

[0101] Note: The pH of the above latexes was adjusted to 10.5 with 5% KOH solution. DCP is diisopropylbenzene peroxide.

[0102] In Example 6 to Example 11, latex solutions were prepared according to the above ratios, and then vulcanized for 24 hours at room temperature with low speed (rate less than 100 r / min) stirring to allow the co-crosslinking agent emulsion to fully combine with the latex to achieve the purpose of vulcanization. Then, gloves were prepared using a glove mold by a dipping method.

[0103] The performance of the gloves was tested, and the experimental results are shown in Table 3: The tensile strength and elongation at break were measured according to the determination method specified in HG / T 2580-2008 Rubber or plastic coated fabric tensile strength and elongation at break. Table 3 Glove performance test table

[0104] Tensile strength / MPa Elongation at break % Example 6 29.48 525.8 Example 7 36.34 509.8 Example 8 34.86 546.4 Example 9 39.39 508.2 Example 10 36.34 513.9 Embodiment 11 35.41 497

[0105] It can be seen from the data in Table 3 that after vulcanizing latex with the aid of cross-linking agent emulsion for latex vulcanization prepared by the present invention, the molding performance of the latex is significantly improved, and the tensile strength of the gloves prepared in Examples 7 to 11 is stronger than that of the gloves prepared in Example 6. In addition, in Example 6, the aid of cross-linking agent emulsion for latex vulcanization prepared by the present invention is not added, and the gloves prepared have odor, while Examples 7 to 11 have no odor.

[0106] In summary, the cross-linking agent emulsion for latex vulcanization prepared by the present invention using a cross-linking agent, an emulsifier, a solvent, an antifreeze agent, an auxiliary agent and water has a small particle size, good stability, a long storage time, is used with an organic peroxide emulsion, has a small amount of addition, significantly improves the degree of cross-linking and the depth of cross-linking, eliminates the peculiar smell generated by some peroxides such as DCP cross-linking, improves the quality of the product, and improves the performance of the product. Therefore, the present invention effectively overcomes various shortcomings in the prior art and has a high industrial utilization value.

[0107] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A cross-linking agent emulsion for latex vulcanization, characterized in that: At least the following weight ratios are included: Cross-linking agent 20% to 50%; Emulsifier 0.5% to 15%; Solvent 5% to 30%; Antifreeze 1% to 10%; Auxiliary additives 0.1% to 2%; Water 23%~48.4%.

2. The cross-linking aid emulsion for latex vulcanization according to claim 1, characterized in that: The auxiliary crosslinking agent is selected from one or more of trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, ethylene glycol diacrylate, ethylene glycol dimethacrylate, N,N′-p-phenyl bismaleimide, zinc diacrylate, zinc dimethacrylate, triallyl cyanurate, triallyl isocyanurate, and 1,2-polybutadiene.

3. The cross-linking aid emulsion for latex vulcanization according to claim 1, characterized in that: The emulsifier is selected from one or more of anionic emulsifiers, cationic emulsifiers, nonionic emulsifiers, and polymer emulsifiers.

4. The cross-linking aid emulsion for latex vulcanization according to claim 1, characterized in that: The solvent is selected from one or more of isododecane, odorless petroleum solvent oil, petroleum solvent oil type aliphatic, aliphatic dibasic acid esters, phthalates, polybenzoates, benzoates, polyol esters, chlorinated hydrocarbons, epoxies, citrates, and polyesters.

5. The cross-linking aid emulsion for latex vulcanization according to claim 1, characterized in that: The antifreeze agent is selected from one or more of ethylene glycol, 2-propanol, 1-propanol, propane-1,2-diol, propane-1,3-diol, glycerol, butane-1-ol, butane-2-ol, butane-1,3-diol, butane-1,4-diol, diethylene glycol, and triethylene glycol.

6. The cross-linking aid emulsion for latex vulcanization according to claim 1, characterized in that: The auxiliary agent is selected from one or more of a pH regulator, a thickener, and a preservative.

7. The cross-linking aid emulsion for latex vulcanization according to claim 6, characterized in that: The pH regulator is selected from inorganic bases or organic amines; And / or, the thickener is selected from one or more of cellulose, bentonite, and xanthan gum; And / or, the preservative is selected from one or more of formaldehyde, chloromethylisothiazolinone, methylisothiazolinone, benzisothiazolinone and methylisothiazolinone.

8. The method for preparing the auxiliary cross-linking agent emulsion for latex vulcanization according to any one of claims 1 to 7, characterized in that: The following steps are involved: 1) adding the cross-linking agent, emulsifier, solvent, antifreeze agent and the first part of auxiliary additives according to the formula amount to the first part of water to obtain a mixed solution; 2) heating the mixed solution, stirring the mixture for reaction, homogenizing and emulsifying to obtain an emulsion; 3) Cooling the emulsion, adding the second part of the auxiliary agent and the second part of water during the cooling process until the temperature drops to room temperature, to obtain a cross-linking agent emulsion.

9. The method for preparing the cross-linking aid emulsion for latex vulcanization according to claim 8, characterized in that: In step 2), the heating is water bath heating; And / or, in step 2), the heating temperature is 30-70°C; And / or, in step 2), the stirring reaction time is 10 to 30 minutes; And / or, in step 2), the stirring rate of the stirring reaction is <1000 r / min; And / or, in step 2), the homogenization is carried out in a homogenizer with a rotation speed of 7000-15000 r / min; And / or, in step 2), the emulsification time is 5 to 60 minutes; And / or, in step 3), the cooling is cooling while stirring, and the stirring rate is less than 1000 r / min; And / or, in step 1) and step 3), the weight ratio of the first part of the auxiliary auxiliary agent to the second part of the auxiliary auxiliary agent is (0-2.5):(0-3), and the weight ratio of the first part of the auxiliary auxiliary agent to the second part of the auxiliary auxiliary agent is not 0 at the same time; And / or, in step 1), the first part of the auxiliary agent is selected from a pH regulator; And / or, in step 3), the second part of the auxiliary agent is selected from one or more of a thickener and a preservative; And / or, in step 1) and step 3), the weight ratio of the first part of water to the second part of water is (50-175):(35-50).

10. Use of the auxiliary cross-linking agent emulsion for latex vulcanization according to any one of claims 1 to 7 in latex vulcanization, characterized in that: The auxiliary cross-linking agent emulsion for latex vulcanization is used in combination with an organic peroxide emulsion to vulcanize the latex, and the weight ratio of the auxiliary cross-linking agent emulsion for latex vulcanization to the organic peroxide emulsion is 20-25:10-15.

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