Shandong Landun Petroleum Resin Co., Ltd.
Add：Guyun Industrial Park, Liaocheng City, Shandong Province
1. Softening point
The temperature at which the resin deforms under a given thermal load. The softening point gives an index of the viscosity in the resin, which is controlled by the average molecular weight of the oligomer. The softening point of the resin is generally determined by the relative molecular weight of the resin and the structure of the resin. The larger the relative molecular mass, the higher the specific gravity of the ring structure, and the higher the softening point of the petroleum resin. The softening point of petroleum resin is about 40-50°C higher than the glass transition temperature Tg, the Tg point of carbon five petroleum resin is about 20°C or more, and the Tg point of NR is about -70°C. The significance of the softening point to customers is that it reflects the melt properties of the polymer and helps customers get the most suitable product formula at the required use temperature. That is to say, the most suitable initial viscosity of the product under the required use temperature. The higher the softening point of petroleum resin, the higher the cohesive strength of the resin.
When the resin component contains higher polar functional groups or double bonds or triple bonds, it is easy to produce a darker color. Therefore, when the formula contains non-hydrogenated hydrocarbon resins, natural rosin and terpene derivatives and other more polar raw materials, the color will usually be darker than that of the hydrogenated composition. There are double bonds in the molecular chain of petroleum resin, and yellow light can pass through, so it looks yellow. The double bond can be saturated by hydrogenation, and the petroleum resin looks water-white. When the resin reacts with oxygen in the air at high temperatures, the color of the resin may become darker, which means that the initial properties of the product have decreased. Because the oxygen molecule has a strong attraction, it can easily grab the weakest atoms in the molecular chain at high temperatures, which may lead to the formation of conjugated large π bonds on the molecular chain, making the resin look yellower. The meaning of resin color to customers: ***The main thing is the thermal yellowing resistance and aging resistance of the resin.