| EPDM products possess outstanding performance and find extensive application across various industries,including the automobile,construction,and cable sectors.As the economy and society continue to progress,China has placed a progressively greater emphasis on environmental concerns.Stated differently,while promoting green production practices,the country has concurrently imposed more stringent requirements on EPDM products.While advocating green production,the country has also put forward higher requirements for EPDM products.Basalt fiber,as a green environmental protection material in the 21 st century,is a competitive new material industry for the sustainable development of the world’s high-tech fiber industry.The BF/EPDM composite made by adding basalt fiber as reinforcement into EPDM matrix can organically combine the high elasticity of rubber with the high modulus and high strength of fiber,giving the composite more excellent performance.Although BF has a series of excellent properties,it also has the characteristics of smooth surface,easy agglomeration and incompatibility with rubber matrix.In order to enhance the overall performance of the BF/EPDM composite,it is important to carry out specific surface treatments on the basalt fibers.This will help to improve the adhesion between the fibers and the EPDM material,leading to better mechanical properties and other desirable characteristics in the final composite product.At the same time,due to the anisotropy of BF,it is only when BF is aligned uniformly that it can play a role of skeleton filling in the EPDM matrix.Therefore,it is necessary to study the orientation of BF in EPDM matrix in order to improve the comprehensive performance of the composite material.Based on the above issues,this article conducts mechanism and experimental research on basalt fiber reinforced rubber composite materials using EPDM as the matrix.The main tasks are as follows:1.Studied the pre-treatment method of BF surface,aimed at the smooth and easily agglomerated characteristics of BF surface,and studied the effect of alkali corrosion of BF in Na OH solution on the comprehensive properties of BF/EPDM composite materials.The SEM analysis results showed that after alkali etching pretreatment,grooves and grooves appeared on the surface of BF,increasing the specific surface area and mechanical locking sites compatible with the EPDM matrix.Simultaneously increase the contact area between BF and subsequent surface treatment reagents.2.A study was conducted on the process method of surface treatment of BF using zirconate coupling agent and sodium carboxymethyl cellulose(CMC).We investigated the surface treatment mechanisms of zirconium ester coupling agent solution and CMC solution,as well as the effects of different concentrations on the properties of BF/EPDM composite materials;SEM analysis found that there were obvious adhesive hangings on the surface of BF at the brittle fracture point,and there were no obvious pores in the rubber matrix.Both the zirconium ester coupling agent and CMC on the surface were successfully grafted onto the BF surface.Among them,a 10% concentration of zirconium ester coupling agent solution had the best effect on treating BF,and a 0.5%concentration of CMC solution had the best effect on treating BF,thus solving the problems of smooth surface,easy aggregation,and difficulty in bonding with the rubber matrix of BF.3.The effects of the length and dosage of BF on the comprehensive properties of BF/EPDM composites were studied.Compared with EPDM without BF addition,the tensile strength and tear resistance of BF/EPDM rubber composites with BF addition decreased,and with the increase of BF addition,the tensile and tear resistance of BF/EPDM composites decreased significantly.However,compared to EPDM without BF addition,the DIN wear and loss factor tan of BF/EPDM composite materials δ There is a trend of first decreasing and then increasing.Among them,when the BF length is3 mm and the number of parts added is 6phr,the comprehensive performance of the BF/EPDM composite material is the best,with a decrease of 3.4% in DIN wear.4.The radial orientation mechanism of BF in EPDM matrix was studied.Based on a dam expansion die and using ANSYS POLYFLOW finite element analysis software,the pressure field,velocity field,and shear rate field of BF/EPDM composite material in the fully filled flow channel of the extrusion die were simulated.The simulation analysis results showed that there was a certain angle between the velocity field and the shear rate field,indicating that BF in the flow channel of the extruder head successfully achieved radial orientation in the EPDM matrix.5.Studied the processing technology and methods of BF/EPDM composite materials.Three BF/EPDM composites with different orientation directions were prepared using a combination of zirconium ester coupling agent for BF and CMC surface treatment methods,using open refining and extrusion processes.The experimental results show that the comprehensive performance of BF/EPDM composite material prepared by surface treatment with 10% zirconium ester coupling agent solution is better,and the BF length is 3mm,the addition amount is 6phr,and the BF/EPDM composite material prepared by radial orientation in its rubber matrix has the best comprehensive performance;Compared with the BF/EPDM composite material that has only undergone alkali corrosion pretreatment and has not been radially oriented in the rubber matrix,its tensile strength has been increased by 17%,tear strength performance has been improved by 6.7%,DIN wear has been reduced by 10.1%,Payne effect has been significantly weakened,and the loss factor tan δ reduce. |
