阅读说明：本技术 一种浸渍芳酰胺橡胶基特种材料及其制备方法 (Special material for dipping aramid rubber base and preparation method thereof ) 是由 姚敏 方祥 张玉柱 于 2019-10-17 设计创作，主要内容包括：本发明公开了一种浸渍芳酰胺橡胶基特种材料,包括原料芳酰胺短纤维、天然橡胶、炭黑、硬脂酸、氧化锌、促进剂、硅酮粉、石英粉、二硫化钼和硫磺,还公开了浸渍芳酰胺橡胶基特种材料的制备方法,包括以下制备步骤：步骤一：剪切；步骤二：预处理；步骤三：辐照接枝；步骤四：浸胶；步骤五：制备混炼胶；步骤六：制备半成品浸渍芳酰胺橡胶基特种材料；步骤七：硫化。本发明针对现有技术中芳酰胺纤维与橡胶的复合材料耐磨性能差、机械强度低等技术问题进行改进,本发明具有提高芳酰胺纤维与橡胶复合材料的耐磨性能和机械强度的优点。(The invention discloses an aromatic polyamide rubber-impregnated special material which comprises raw materials of aromatic polyamide short fibers, natural rubber, carbon black, stearic acid, zinc oxide, an accelerator, silicone powder, quartz powder, molybdenum disulfide and sulfur, and also discloses a preparation method of the aromatic polyamide rubber-impregnated special material, which comprises the following preparation steps: the method comprises the following steps: shearing; step two: pre-treating; step three: carrying out irradiation grafting; step four: dipping glue; step five: preparing rubber compound; step six: preparing a semi-finished product of the dipping aramid rubber-based special material; step seven: and (4) vulcanizing. The invention improves the technical problems of poor wear resistance, low mechanical strength and the like of the composite material of the aramid fiber and the rubber in the prior art, and has the advantage of improving the wear resistance and the mechanical strength of the composite material of the aramid fiber and the rubber.)

1. The special material for dipping the aramid rubber is characterized by comprising raw materials of aramid short fiber, natural rubber, carbon black, stearic acid, zinc oxide, an accelerator, silicone powder, quartz powder, molybdenum disulfide and sulfur, wherein the aramid short fiber, the natural rubber, the carbon black, the stearic acid, the zinc oxide, the accelerator, the silicone powder, the quartz powder, the molybdenum disulfide and the sulfur comprise the following components in parts by weight:

the length of the aramid short fiber is 2-3 mm, and the accelerator is NS, DM, PZ, PX or NA-22.

2. The process for the preparation of an aramid impregnated rubber-based specialty material as claimed in claim 1 comprising the steps of:

the method comprises the following steps: shearing, namely shearing the aramid fibers by using a fiber shearing machine to obtain the aramid short fibers;

step two: pre-treating;

firstly, putting the aramid short fiber into an acetone solution, stirring and cleaning for 20-30 min;

then, putting the aramid short fibers into distilled water, stirring and cleaning for 10-20 min;

finally, the aramid short fibers are placed in a vacuum drying oven to be dried, and the pretreated aramid short fibers are obtained;

step three: performing irradiation grafting, namely performing irradiation grafting treatment on the pretreated aramid short fiber by adopting an electron beam to obtain aramid irradiation grafted short fiber;

step four: dipping in glue, namely dipping the aromatic amide irradiation grafted short fiber into a dipping solution for 30-40 min to obtain the aromatic amide dipped short fiber, wherein the solid content of the dipping solution is 5-10%, the dipping solution comprises raw materials of resorcinol, phenolic resin, ethylene propylene diene monomer latex, caustic soda, isocyanate, sodium dodecyl benzene sulfonate, hydrogenated rosin glyceride and deionized water, and the resorcinol, the phenolic resin, the ethylene propylene diene monomer latex, the caustic soda, the isocyanate, the sodium dodecyl benzene sulfonate, the hydrogenated rosin glyceride and the deionized water comprise the following components in parts by weight:

step five: preparing rubber compound;

firstly, adding the natural rubber into a mixing roll, heating and softening, and then cooling to 60-70 ℃;

then, sequentially adding the aramid impregnated short fiber, carbon black, silicone powder, quartz powder, molybdenum disulfide, stearic acid, zinc oxide and an accelerator into the mixing roll, stirring and mixing uniformly, and standing for 2-3 h;

then, adding the sulfur into the mixing roll, uniformly stirring and mixing, and standing for 7-8 hours to obtain the rubber compound;

step six: preparing a semi-finished product dipping aramid rubber-based special material, extruding the mixed rubber through a double-screw extruder, and then preparing the semi-finished product dipping aramid rubber-based special material through an injection molding process;

step seven: and (4) vulcanizing, namely vulcanizing the semi-finished product impregnated aramid rubber-based special material by using a flat vulcanizing machine to obtain the impregnated aramid rubber-based special material.

3. The method for preparing the special material for dipping the aramid rubber as claimed in claim 2, wherein in the second step, the temperature in the vacuum drying oven is 80-90 ℃ and the drying time is 30-50 min.

4. The method for preparing a specialty material impregnated with aramid rubber as claimed in claim 2 wherein in step three, said radiation grafting comprises the specific steps of:

firstly, putting the pretreated aramid fiber into a vacuum glass container;

subsequently, injecting nitrogen into the vacuum glass container, and sealing;

irradiating the pretreated aramid short fiber by using an electron beam generated by an electron accelerator, wherein the distance between the electron accelerator and the aramid short fiber is 30-60 cm;

then, adding a grafting agent and an initiator into the vacuum glass container, and immersing the pretreated aramid short fibers in a mixed solvent of the grafting agent and the initiator;

and finally, heating the mixed solvent of the grafting agent and the initiator to 50-60 ℃ and maintaining for 2-3 h.

5. The method for preparing the aramid impregnated rubber-based specialty material as claimed in claim 4, wherein the energy of said electron beam is 5-8 MeV, the average beam current of said electron beam is 20-30 mA, and the irradiation dose is 30-110 kGy.

6. The process for the preparation of impregnated aramid rubber-based specialty material as claimed in claim 4 wherein said grafting agent is KH570, KH560, triallyl isocyanurate or epichlorohydrin.

7. The method of claim 4 wherein said initiator is benzoyl peroxide, dicumyl peroxide, azobisisobutyronitrile, potassium persulfate or cyclohexanone peroxide.

8. The method for preparing the impregnated aramid rubber-based specialty material of claim 2, wherein in step four, the solids content of resorcinol is 20-30%, the solids content of ethylene-propylene-diene monomer latex is 40-50%, the solids content of phenolic resin is 5-7%, the concentration of caustic soda is 80-90%, and the solids content of isocyanate is 10-20%.

9. The method for preparing the special material for rubber-impregnated aramid rubber according to claim 2, wherein in the seventh step, the vulcanization temperature is 110 to 130 ℃, the vulcanization pressure is 9 to 12Mpa, and the vulcanization time is 30 to 45 min.

Technical Field

The invention relates to the technical field of rubber composite materials, in particular to an aramid impregnated rubber-based special material and a preparation method thereof.

Background

The rubber composite material is mainly composed of a framework material and an elastic rubber matrix, compared with thermosetting and thermoplastic polymer composite materials, the rubber composite material has a larger deformation range, higher bearing capacity and good fatigue resistance, the performance and the service life of the framework material play a decisive role in the overall performance in the rubber composite material, the rubber composite material in the prior art mainly takes glass fiber, aramid fiber, carbon fiber, polyethylene fiber and the like as the framework material, and the aramid fiber belongs to one of the aramid fibers. The composite material of aramid fiber and rubber in the prior art has the problems of poor wear resistance and poor mechanical strength.

Aiming at the technical problems, the invention discloses an aramid impregnated rubber-based special material and a preparation method thereof, and the aramid impregnated rubber-based special material has the advantages of improving the wear resistance and mechanical strength of aramid fiber and rubber composite materials.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides an aramid impregnated rubber-based special material and a preparation method thereof, so as to solve the technical problems of poor wear resistance, poor mechanical strength and the like of a composite material of aramid fibers and rubber in the prior art, and the aramid impregnated rubber-based special material has the advantage of improving the wear resistance and mechanical strength of the aramid fibers and rubber composite material.

The invention is realized by the following technical scheme: the invention discloses an aramid rubber impregnated special material which comprises the following raw materials of aramid short fiber, natural rubber, carbon black, stearic acid, zinc oxide, an accelerator, silicone powder, quartz powder, molybdenum disulfide and sulfur, wherein the aramid short fiber, the natural rubber, the carbon black, the stearic acid, the zinc oxide, the accelerator, the silicone powder, the quartz powder, the molybdenum disulfide and the sulfur comprise the following components in parts by weight:

the length of the aramid short fiber is 2-3 mm, and the accelerator is NS, DM, PZ, PX or NA-22.

The invention also discloses a preparation method of the special material for dipping the aramid rubber base, which comprises the following preparation steps:

the method comprises the following steps: shearing, namely shearing the aramid fibers by using a fiber shearing machine to obtain aramid short fibers;

step two: pre-treating;

firstly, putting aramid short fibers into an acetone solution, stirring and cleaning for 20-30 min;

then, putting the aramid short fibers into distilled water, stirring and cleaning for 10-20 min;

finally, putting the aramid short fiber into a vacuum drying oven for drying to obtain pretreated aramid short fiber;

step three: performing irradiation grafting, namely performing irradiation grafting treatment on the pretreated aramid short fiber by adopting an electron beam to obtain aramid irradiation grafted short fiber;

step four: dipping in glue, namely dipping the aromatic amide irradiation grafted short fiber into a dipping solution for 30-40 min to obtain the aromatic amide dipped short fiber, wherein the solid content of the dipping solution is 5-10%, the dipping solution comprises raw materials of resorcinol, phenolic resin, ethylene propylene diene monomer latex, caustic soda, isocyanate, sodium dodecyl benzene sulfonate, hydrogenated rosin glyceride and deionized water, and the resorcinol, the phenolic resin, the ethylene propylene diene monomer latex, the caustic soda, the isocyanate, the sodium dodecyl benzene sulfonate, the hydrogenated rosin glyceride and the deionized water are as follows by weight:

step five: preparing rubber compound;

firstly, adding natural rubber into a mixing roll, heating for softening, and cooling to 60-70 ℃;

then, sequentially adding aramid impregnated short fibers, carbon black, silicone powder, quartz powder, molybdenum disulfide, stearic acid, zinc oxide and an accelerator into a mixing roll, stirring and mixing uniformly, and standing for 2-3 hours;

then adding sulfur into the mixing roll, stirring and mixing uniformly, and standing for 7-8 h to obtain a rubber compound;

step six: preparing a semi-finished product of the aramid rubber base impregnated special material, extruding the mixed rubber through a double-screw extruder, and then preparing the semi-finished product of the aramid rubber base impregnated special material through an injection molding process;

step seven: and (4) vulcanizing, namely vulcanizing the semi-finished product impregnated aramid rubber-based special material by using a flat vulcanizing machine to obtain the impregnated aramid rubber-based special material.

Preferably, in order to better dry the aramid short fiber and improve the subsequent irradiation grafting effect, in the second step, the temperature in the vacuum drying oven is 80-90 ℃, and the drying time is 30-50 min.

Preferably, in order to modify the pretreated aramid short fiber, an active group is introduced to the surface of the pretreated aramid short fiber to improve the adhesive force between the pretreated aramid short fiber and a dipping solution, and in the step three, the irradiation grafting comprises the following specific steps:

firstly, putting the pretreated aramid fiber into a vacuum glass container;

then, injecting nitrogen into the vacuum glass container, and sealing;

irradiating the pretreated aramid short fiber by using an electron beam generated by an electron accelerator, wherein the distance between the electron accelerator and the aramid short fiber is 30-60 cm;

then, adding a grafting agent and an initiator into a vacuum glass container, and immersing the aramid short fiber in a mixed solvent of the grafting agent and the initiator for pretreatment;

and finally, heating the mixed solvent of the grafting agent and the initiator to 50-60 ℃ and maintaining for 2-3 h.

Preferably, in order to improve the irradiation effect, the energy of the electron beam is 5-8 MeV, the average beam current of the electron beam is 20-30 mA, and the irradiation dose is 30-110 kGy.

Preferably, the grafting agent is KH570, KH560, triallyl isocyanurate or epichlorohydrin in order to increase the grafting effect.

Preferably, in order to enhance the grafting effect, the initiator is benzoyl peroxide, dicumyl peroxide, azobisisobutyronitrile, potassium persulfate or cyclohexanone peroxide.

Preferably, in order to improve the gum dipping effect, in the fourth step, the solid content of the m-diphenol is 20-30%, the solid content of the ethylene propylene diene monomer latex is 40-50%, the solid content of the phenolic resin is 5-7%, the concentration of the caustic soda is 80-90%, and the solid content of the isocyanate is 10-20%.

Preferably, in order to improve the vulcanization effect and the performance of the aramid fiber and rubber composite material, in the seventh step, the vulcanization temperature is 110-130 ℃, the vulcanization pressure is 9-12 MPa, and the vulcanization time is 30-45 min.

The invention has the following advantages: the invention firstly cuts aramid fiber to obtain aramid short fiber, then pretreats the aramid short fiber to remove short floc, dust and other impurities on the surface of the aramid short fiber, then carries out irradiation grafting treatment, introduces active groups on the surface of the aramid short fiber, then immerses the aramid short fiber after irradiation grafting treatment in a dipping solution, finally adds the aramid short fiber after dipping treatment as a raw material of rubber compound into the rubber compound, and simultaneously adds silicone powder and quartz powder into the rubber compound, wherein the silicone powder has the functions of reducing the friction coefficient of the composite material, improving the smoothness of the composite material, improving the surface gloss of the composite material and enhancing the silky touch feeling of the composite surface, thereby enhancing the wear resistance and scratch resistance of the composite material, and the quartz powder is a hard, wear-resistant and chemically stable silicate, thereby being capable of obviously improving the wear resistance and the mechanical strength of the composite material. The invention also adds sodium dodecyl benzene sulfonate and hydrogenated rosin glyceride into the gum dipping solution, the sodium dodecyl benzene sulfonate can improve the surface tension among various constituent phases in the gum dipping solution, so as to form a uniform and stable dispersion system or emulsion, thereby the gum dipping solution can be fully adhered to the surface of the aramid fiber after irradiation grafting treatment, the hydrogenated rosin glyceride can increase the viscosity of the gum dipping solution, thereby the adhesive force between the aramid fiber and rubber is improved, and the special material for dipping aramid rubber prepared by the invention has the advantages of good wear resistance, high mechanical strength and the like.

Detailed Description

The following examples are given for the detailed implementation and specific operation of the present invention, but the scope of the present invention is not limited to the following examples.