Balance Between Low Temperature And Room Temperature Of Hot Melt Pressure Sensitive Adhesive

Hot melt adhesives can show excellent adhesion properties at room temperature, such as exploitative force, initial adhesion, etc., but the performance at low temperatures is not ideal. This is mainly due to the sensitivity of hot melt pressure-sensitive adhesives to ambient temperature. In general, most hot melt pressure sensitive adhesives are designed for room temperature conditions of 25°C, but the market is unlikely to accept pressure sensitive adhesives from suppliers for specific temperature conditions. Therefore, a thermobaric sensitizer over a wide temperature range is required. The most important issue in the design of hot melt pressure sensitizers with such a wide temperature range is the glass transition temperature. Most general-purpose hot melt sensitizers used at room temperature are generally glass transition temperatures of 0-10°C. The low-temperature adhesion properties of hot melt pressure sensitizers require a reduction in the glass transition temperature. However, the flow/wetting properties of this adhesive are reduced at room temperature, which means that the performance of pressure-sensitive adhesives is reduced. Based on the above explanation, theoretically, no hot pressing sensitive adhesive can guarantee excellent adhesive performance at both room and low temperatures. However, when it comes to design techniques, we can strike a balance through the following three aspects. First, we can choose an elastomer with an appropriate cross-sectional ratio to make the rubber phase composition as high as possible; The second is to choose an elastomer with a wide molecular weight distribution. Third, the adhesive is selected to form 2 glass transition temperature points.