We all know that the main material of tires is natural rubber,and there is a gap between unprocessed rubber and tires in terms of durability,grip,puncture resistance and many other performance requirements.Therefore,when manufacturing tires,different additives in different doses must be added to meet the design and use requirements.

1）Tire additives-coumarone resin

Coumarone resin has good compatibility with rubber and is a solvent-based tackifier,plasticizer and softener.Liquid products are good tackifiers with slightly lower reinforcement;solid products,especially high softening point products,are better reinforcing agents that can improve the mechanical and physical properties and aging resistance of rubber,but the viscosity is not as good as liquid coumarone resin.It can dissolve sulfur,help disperse sulfur and carbon black,and prevent scorching.Coumarone can make rubber have the properties of viscosity increase,reinforcement,cut resistance,tensile resistance,wear resistance,increased toughness,increased hardness,etc.,so as to meet the needs of tire manufacturing.

2）Accelerator

Mainly used in radial tires,one is as a curing agent for reinforcing resin to increase the hardness of rubber products;the other is to form a bonding system together with additives such as resorcinol,which plays an important role in the bonding of rubber and fiber.Among them,accelerators can promote vulcanization.It can shorten the vulcanization time or reduce the vulcanization temperature,reduce the amount of vulcanizer and improve the physical and mechanical properties of rubber.

3）Zinc oxide

Zinc oxide is one of the raw materials for rubber manufacturing.The mixture of zinc oxide and another additive,stearic acid,enhances the hardening degree of rubber.In the manufacture of automobile tires,zinc oxide can greatly improve the thermal conductivity of rubber,thereby helping the tire to dissipate heat and ensure driving safety.Zinc oxide additives also prevent mold or ultraviolet rays from eroding rubber.

4）Carbon black

The finer the particle size of carbon black used in tire manufacturing,the better its reinforcing performance;the higher the carbon black structure,the higher its tensile stress and modulus.Fine-particle reinforcing varieties are mainly used for tire treads,giving tires excellent wear resistance.Other parts of the tire,such as the sidewall,cord layer,belt buffer layer and inner liner,require the rubber to be resistant to flex cracking,ozone oxidation,good resilience and low heat generation.Generally,coarser particle size semi-reinforced(specific surface area less than 40m2/g)furnace black is selected.

5）Precipitated Silica

slica has and silane coupling agents are used in tire tread rubber.While reducing the rolling resistance of the tire,it can improve the wear resistance and wet skid resistance of the tire.The tensile strength,tear strength and wear resistance of the rubber compound using white carbon black are all improved,and it has more advantages in transparent and colored rubber products.

6）Aromatic oil of tire additives

Aromatic oil has good compatibility with black rubber,and can also improve rubber elasticity and toughness,especially good affinity with natural rubber and butadiene rubber,good dispersibility of compounding agents,and has a good effect on the calendering and extrusion processing of rubber.In tire manufacturing,a kind of polycyclic aromatic hydrocarbons,also known as polycyclic aromatic compounds or polycyclic aromatic hydrocarbons,is added.But it has been defined as a carcinogen.Clinical experiment reports point out that long-term exposure to high-concentration mixtures of polycyclic aromatic compounds can cause diseases such as skin cancer,lung cancer,stomach cancer and liver cancer.