In the absence of UV irradiation, a mixing time of 2 h did not significantly change the viscosity of the pure NR latex (no
photoinitiator and coagent present). The viscosity of the latex before and after being continuously mixed for 2 h was about
60.0 mPa·s. In the presence of the coagent and the photoinitiator, the viscosity of the nonirradiated latex mixture notably increased from an initial value of 60.0 mPa·s to a value of 77.5 mPa·s at 2 h. Thus, this viscosity increase is strongly suggestive of chain entanglement induced by the presence of the coagent and the photoinitiator.