Evaluation of novel synthetic conditioning polymers for shampoos.
Cationic polymers have traditionally been used in shampoo formulations to impart conditioning properties to hair. In this study, commercial synthetic cationic polymers were investigated using coacervate formation, objective wet comb analysis, silicone deposition and panel studies to determine structure function properties with the goal of developing novel conditioning polymers. New polymers were synthesized and, based on criteria determined in the first part of the study, found to have marginal improvement over existing synthetic cationic conditioning polymers. A novel experimental polymer developed for a different industry was also investigated for conditioning properties. This polymer showed significant enhancement of silicone deposition over current commercial polymers, including cationic guar, even at significantly reduced silicone and polymer concentrations. The experimental polymer exhibited parity or improvement over benchmark polymers in panel studies, and similar performance to other synthetic polymers in objective wet comb studies.
Effect of hydrophobic substitution on cationic conditioning polymers
Cationic cellulosic polymers are formulated with anionic surfactants in shampoos and body washes as conditioners and deposition aids. During dilution, the polymer and surfactant undergo a series of association and microstructure changes: from a condensed network to globular aggregation to inter-chain association with micelles. Cationic polymer structure impacts the polymer/surfactant interaction. The addition of hydrophobic chains on the polymers significantly changes deposition and conditioning properties. In general, deposition of benefit agents from shampoos and body washes increases in the presence of these modified polymers. Conditioning in clear formulations also improves. These performance changes depend on the absolute molar substitution of the hydrophobic moiety as well as the surfactant system. The presence of even very low levels of hydrophobe alters interfacial reactivity with surfactants and surfaces influencing both coacervate formation and deposition.
Finite Difference Modeling on the Temperature Field of Substrate in Friction Surfacing
Friction surfacing is an advanced process of great potential, especially in the field of repair and reclamation of worn and damaged components. As a kind of thermal processing technology, the temperature profile and changes of the substrate in friction surfacing are important factors to get coatings of high quality. In this paper, the temperature field of the substrate during the process is simulated by finite difference method. The results are consistent with experiments, reappearing the temperature change of the substrate during friction surfacing, allowing further study on figuration and quality of coatings.