| In this paper, the surfactant octadecyl amine polyoxyethylene ether (a long chain ethoxyl-ated fatty amine, refered to as the ether amine 1805) as a raw material, the ether amine oxide 1805, referred to as OA-1805, was prepared by H2O2 oxidation reaction with high conversion, and its structure was characterized by FTIR and API-ES. OA-1805, which wasn’t undergo any operation for the purification, was applied to regulate the emulsion homopolymerization react-ion of styrene or isoprene and the copolymerization of styrene and butadiene by the redox ini tiator system ammonium persulfate (APS) and a tertiary amine polyoxyethylene ether,without any chain transfer agents, buffers for polymerization. Synthetic PS, PI and ESBR was researched by FTIR,1H-NMR,13C-NMR, GPC, DSC, et.Emulsion polymerization regulated by OA-1805 can be carried out at low temperature by making use of the amine redox system APS/ether amine, APS/ether diamine (propionyl dia-mine) priming activity is much higher than APS/ether monoamines (1805), and St polymerization activity is far higher than IP. This emulsion polymerization system had a certain time of induction period, and it has been shortened with the increase of polymerization temperature.OA-1805 regulated emulsion polymerization with the redox system APS and 1805 or propionyl diamine, were available to synthesized PS respectively at low temperature 10℃,0℃. The polymers obtained were all atactic polystyrene. In APS/1805 system, the polystyrene molecular weight distribution was narrow (PDI≈1.4), and the ultra-high molecular weight up to 2.0×106; in the APS/propionyl diamine system system, the molecular weighto of the polystyrene was lower, only 5.8 × 105, PDI was slightly smaller than 2.0, that was mainly due to the synergistic effect between APS and two nitrogen atoms of propionyl diamine, which could produce large amounts of primary radicals in a short time. In addition, the presence of propionyl diamine caused greater the steric hindrance. And so,the regulatory capacity of OA-1805 was reduced, and the characteristics of living polymerization was weaker.OA-1805 regulated emulsion polymerization with the redox system APS and 1805 or propionyl diamine, could successfully synthesized Polyisoprene at 20℃. After 24 hours, the conversation reached about 20.0%. Microstructure content of polyisoprene as follows: Trans-1,4/Cis-1,4≈63.1%/22.2%; 3,4-PI≈10.6%;1,2-PI≈4.0%. PI weight average molecular weight was about 5.0×105 to 7.0×103, and molecular weight distribution was wide relatively, in the APS/1805 system, PDI=1.8-2.3; in the APS/propionyl diamine system, PDI>2.3. The presence of side chain structure and crosslinking, brought certain restrictions to the regulation of OA-1805 for the emulsion polymerization of isoprene. Compared with conventional emulsion polymerization on the molecular weight distribution, OA-1805 played a certain weak role in regulating in emulsion polymerization of isoprene. Namely the regulation of OA-1805 for the monomer having a certain selectivity, relative to isoprene monomer the regulatory role was weaker.OA-1805 regulated emulsion polymerization with the redox system APS and propionyl diamine, was available to synthesized ESBR at 5℃. Microstructure content of ESBR obtained as follows:St≈13.6%; trans/cis-72.9%/11.4%; 1,2-PB≈15.7%. The molecular weight was low(Mw≈3.2×105～3.8×105), and the molecular weight distribution was about 2.3. Compared with the conventional low temperature ESBR, this system avoids the use of a molecular weight modifier such as mercaptan, and thus more secure and environmental.The results showed that the amine oxide OA-1805 regulation emulsion polymerization system can be prepared UHMWPS with narrow molecular weight distribution, presented certain "living" characteristics. And there are certain regulation effects in isoprene homopoly merization and copolymerization butadiene and styrene under the control of the amine oxide OA-1805 polymerization system. This nitrogen-oxygen bond OA-1805 non-regulatory role for the realization of research activity controlled radical polymerization in emulsion polymerization system provides a new direction. The discovery of this regulation by non chemical bond of amine oxide OA-1805, would provides a new research direction about implement "living"/controlled free radical polymerization in emulsion system. |
