High-temperature resistant polyurethane timing belts are mainly made by selecting special raw materials and optimizing formulas to achieve high-temperature resistance. In terms of raw materials, polyurethane resins with high thermal stability are used. The chemical bond energy in the molecular structure of these resins is high, which can remain relatively stable under high temperature environments and is not prone to thermal decomposition or deformation. At the same time, heat-resistant additives such as certain inorganic fillers and antioxidants are added to the formula. Inorganic fillers can improve the thermal conductivity of the timing belt, allowing heat to dissipate more quickly and avoid local overheating; antioxidants can prevent polyurethane from being oxidized at high temperatures and extend its service life.
In addition, the structure of the timing belt is optimized. For example, a multi-layer composite structure is used, and the middle layer uses high-strength skeleton materials such as glass fiber or aramid fiber. These fibers have good high-temperature resistance and mechanical strength, can withstand tension at high temperatures, and provide stable shape and size for the timing belt.
The realization of anti-static polyurethane timing belts is mainly based on the addition of conductive materials and surface treatment technology. Conductive fillers such as conductive carbon black and carbon fiber are usually added to the polyurethane matrix. These conductive fillers form a conductive network inside the synchronous belt. When the synchronous belt generates static electricity during operation, the static electricity can be quickly conducted to the ground or other grounding devices through the conductive network, thereby avoiding the accumulation of static electricity.
At the same time, the surface of the synchronous belt is specially treated, such as coating with an antistatic coating. This coating has good conductivity and antistatic properties, can timely remove static electricity on the surface of the synchronous belt, and can prevent impurities such as dust from being adsorbed on the surface of the synchronous belt, further reducing the generation of static electricity. In addition, by adjusting the production process of the synchronous belt and controlling the surface resistance of the material to keep it in a suitable range, static electricity can be effectively removed without affecting other properties of the synchronous belt.
When it is necessary to have both high temperature resistance and antistatic functions, first of all, in the selection of raw materials, both high temperature resistant polyurethane resin and the addition of conductive fillers should be considered. In the formulation design, the proportion of various components needs to be balanced to ensure that the conductive performance is not affected while achieving high temperature resistance.
For structural design, in addition to using high temperature resistant skeleton materials, it is also necessary to consider how to better distribute the conductive fillers so that it can still maintain good conductive properties in a high temperature environment. For example, the conductive filler and the skeleton material can be specially composited to improve the bonding force between them and prevent the migration or agglomeration of the conductive filler at high temperature, thereby ensuring the stability of the conductive network.
In terms of production technology, it is necessary to accurately control the parameters of each link, such as temperature, pressure and time. During the high-temperature vulcanization process, it is necessary to ensure that the polyurethane resin is fully cross-linked, and at the same time, the conductive filler is evenly dispersed in the matrix to form a stable conductive structure. In the surface treatment link, it is necessary to ensure the adhesion and stability of the antistatic coating at high temperature, and to make it have a good antistatic effect.
In functional polyurethane timing belts, there is a synergistic effect between various additives. For example, some additives can improve the compatibility between polyurethane resin and conductive filler, so that the conductive filler can be more evenly dispersed in the matrix, thereby improving the conductive performance. At the same time, some additives can also enhance the mechanical properties and high temperature resistance of the timing belt, and work together with other additives to achieve the comprehensive performance improvement of the timing belt.
In addition, some additives can improve the surface properties of the timing belt, make it easier to carry out surface treatment, and improve the adhesion of the antistatic coating. This synergistic effect enables the functional polyurethane timing belt to stably perform its functions such as high temperature resistance and anti-static under different working environments.
Fiber reinforcement plays an important role in high temperature resistant and anti-static polyurethane timing belts. For high temperature resistance, fiber reinforcement can withstand tensile stress under high temperature and prevent the timing belt from excessive elongation or deformation under high temperature. They form a good bonding interface with the polyurethane matrix, which can effectively transfer stress and improve the overall strength and stability of the timing belt.
In terms of anti-static, fiber reinforcement can cooperate with conductive fillers to further improve the conductive network. For example, carbon fiber itself has a certain conductivity, which can form additional conductive channels in the timing belt and enhance the conductivity of static electricity. At the same time, fiber reinforcement can also improve the wear resistance and tear resistance of the timing belt and reduce the generation of static electricity caused by wear and tear.
Surface treatment is crucial to the performance of functional polyurethane timing belts. Anti-static coating can not only conduct static electricity, but also protect the surface of the timing belt from erosion by the external environment, such as dust, oil pollution, etc. These pollutants may affect the surface resistance of the timing belt and cause static electricity accumulation.
For high temperature resistance, surface treatment can improve the thermal stability of the timing belt surface and prevent oxidation and cracking at high temperatures. For example, some surface treatment methods can form a dense protective film on the surface of the timing belt, reduce the impact of heat on the internal materials, and improve the heat dissipation performance of the timing belt.
Accurate production process control is the key to achieving the performance of functional polyurethane timing belts. During the mixing of raw materials, the proportion and mixing time of various components need to be strictly controlled to ensure that additives and conductive fillers are evenly dispersed in the polyurethane matrix. During the molding process, the control of parameters such as temperature, pressure and time directly affects the structure and performance of the timing belt.
For example, too high a temperature may cause excessive cross-linking of the polyurethane resin, making the timing belt hard and brittle; while too low a temperature may cause incomplete cross-linking of the resin, affecting the strength and high temperature resistance of the timing belt. In the surface treatment process, the control of process parameters is also very important, such as the thickness of the coating, the curing temperature and time, etc., which are directly related to the performance and adhesion of the antistatic coating. By accurately controlling each link of the production process, the performance of the functional polyurethane timing belt can be guaranteed to be stable and reliable to meet the needs of different working environments.
