*3.4. Kineticks in RITP Emulsion Copolymerization*

The monomer conversion was increased with time after 40 min, as shown in Figure 5. In the first 40 min of reaction time, the mixture was brown, indicating that iodine was not completely consumed in the induction period.

**Figure 4.** Stress–strain curves of emulsion film with different measured molecular weights.

**Figure 5.** Evolution of monomer conversion versus time for RITP emulsion copolymerization. Conditions: *m*(PEGMA)/ *m*(MAA) = 1/1 and *m*(MAA) + *m*(PEGMA) = 1.664 g; *m*(BA)/m(St) = 1/2; *n*(St)/*n*(HEMA)/*n*(BMA)/*n*(BA)/*n*(ACPA)/ *n*(I2) = 18.36/18.74/40.36/7.46/1.15/1, ammonia solution (0.70 g); *m*(I2) = 0.273 g; *m*(ACPA) = 0.346 g; no MMA in the polymerization system; the total mass of ingredients without ACPA Solution and I2 was maintained at 30.08 g in theory; the reaction time was 210 min.

A sample was withdrawn using a syringe under N2 atmosphere at 53 min, and the mixture solution was brown, indicating that the induction period was more than 53 min. The polymerization was not complete when the monomer conversion was low, and there were odors coming from monomers in the emulsion. Subsequently, a sample was withdrawn at 79 min, and the emulsion was stable and white. This manifests that iodine was completely consumed in 79 min, with the sample exhibiting a certain viscosity. The monomer conversion did not increase obviously after 180 min. The highest monomer conversion was 96.8%. This tendency of the monomer conversion versus time in Figure 5 is similar to that reported in the work by Tonnar [38].

As shown in Figure 6, the evolution of measured *M*<sup>n</sup> versus monomer conversion showed a linear trend, and *Ð* was decreased overall with conversion. The measured *M*n in the withdrawn sample at 79 min (34.6% monomer conversion) was 22,800 g·mol−1, and this value deviated from the trend of the other five *M*<sup>n</sup> values. The overall trend of *M*<sup>n</sup> versus monomer conversion indicated a living polymerization process.

**Figure 6.** Evolution of measured *M*n and *Ð* with monomer conversion for RITP emulsion copolymerization.
