This English website is currently under construction
Curing at room temperature PP adhesive

PP(Polypropylene) and TPO (Thermoplastic olefin) have the advantages of easy molding, chemical resistance and low cost. Its disadvantages are the low polarity of the chemical structure, many are crystalline polymers, which cause bonding difficulties. We are developing acrylic adhesive of free-radical polymerization to solve this problem. Coating the adhesive on the PP test piece (Figure 1), then combine with two test pieces and cured at room temperature (Figure 2). The adhesive was cohesive failure after the tensile test. The horizontal cracked on the rupture surface showed the toughness of the adhesive: As the specimen during stretched, causes the colloid rupture (Figure 3). Adjusting the toughness and stiffness of the adhesive the strength would be different. The specimen of some formulas became white during the tensile testing (Figure 4). This is the result of crystalline orientation in stress. It means that the shear strength of the resin is much stronger than the tensile strength of PP. The shear strength of the PP adhesive was about 35 Kgf / cm2 in the experiment without primer and cured at room temperature (Figure 5). In the future, there remain some problems to be solved, such as the oxygen interference, increasing the strength, apply to other nonpolar materials, etc. We will continue working on.
─ Author: Dr. Wu Jia-xing