Polyethylene Surface Modification by Side Chain Crystalline Block Copolymer

Summary Recently, we found that Side Chain Crystalline Block Co‐Polymer (SCCBC), which has a long alkane side chain (>C10), can be used as a good dispersant for a concentrated polyethylene fine‐particle dispersion. We also found that the viscosity of this concentrated dispersion increased at high temperature and returned to normal at low temperature. We named this fluid Thermal Rheological Fluid (TR Fluid). The mechanism of this phenomenon involves the attachment and detachment of SCCBC. With the use of this mechanism, we examined whether it could be possible to modify the properties of a polyethylene (PE) surface. A PE film was dipped in a dilute SCCBC solution, and its surface was coated by SCCBC. The water contact angle changed from around 90° before coating to around 70° after coating. Thus, the surface of PE was made more hydrophilic. The adhesion strength was examined by a tensile test. The PE film elongated before the attached region broke. These results showed that SCCBC has a very high adhesion strength and can be used as a surface modifier or primer for attachment. Additionally, SCCBC could be easily removed from the PE film by hot water, and thus, it should be very easy to recycle or re‐use the PE.