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Cationic copolymerization of isobutylene and chlorostyrene was investigated using the Lewis acid initiator system. Titanium (IV) chloride (TiCl4) and ethylaluminum sesquichloride (AlEt1.5Cl1.5) were used as the co-initiators, and 2-chloro-2,4,4-trimethylpentane (TMPCl) and H2O were used as the main initiators. The influences of monomer feeding ratio and reaction time were studied. The reaction mechanism was proposed by studying the reaction kinetics. It was found that when p-chloromethylstyrene (p-ClMSt) was used, benzyl chloride was easily involved in the initiation reaction stage, leading to the formation of branched polymer. When p-chlorostyrene (p-ClSt) was used as a co-monomer, living copolymerization was achieved and no branching structure formed. Isobutylene, isoprene, and p-ClSt were synthesized with the AlEt1.5Cl1.5 initiator system. The high-molecular-weight halogenated ternary copolymer was successfully prepared by one-step polymerization. Vulcanization and mechanical property studies were also performed.

Hydroxyl-terminated linear and star-shaped telechelic polyisobutylene have been successfully synthesized by living cationic polymerization using propylene oxide (PO)/Titanium tetrachloride (TiCl4) as the initiator system.

Ionic polymer-Carbon nanotube composite (IPCC) actuators based on black phosphorus (BP)-Nafion composite membranes were fabricated. BP-Nafion composite was used as the ionic matrix with functional ...

Nanostructured polyaniline was prepared using the template method in the mixed solvent that was composed of dimethyl formamide and distilled water. A series of tests were performed to examine the structural and electrical performance of polyaniline, including X-ray diffraction, scanning electron microscopy, Fourier-transform infrared spectrometry, nitrogen adsorption–desorption, cyclic voltammetry and galvanostatic charge–discharge tests. Results indicated that the mixed solvent could lead to a different morphology and influence the electrical performance of polyaniline in the system. The specific surface area of polyaniline was greatly improved and the electrical properties were enhanced correspondingly.

Intelligent nanoparticles with core-shell structure have attracted much attention in the field of drug controlled release. 5-fluorouracil (5-FU) is an anti-metabolic drug that inhibits the formation of pyrimidine nucleotides in tumor cells and has a significant effect on a variety of tumors. However, 5-FU is more toxic and has more harmful reactions. In order to reduce the toxicity, the study of its controlled release system is attracting more and more attention. In this paper, PLA macromolecular monomers with double bond functional groups were prepared by ring-opening polymerization of lactide with hydroxyethyl methacrylate as an initiator. And then, N-isopropylacrylamide (NIPAm) was used as the thermosensitive monomer and methacrylic acid (AA) as the pH sensitive monomer, and the PLA macromonomer was subjected to free radical copolymerization. PH reaction, biodegradable properties of amphiphilic copolymer PLA-g-P(NIPAm-co-AA), and 5-fluorouracil are as a kind of model drug preparation of multi-functional nano-anti-tumor drugs. The results of in vitro drug release showed that PLA-g-P(NIPAm-co-AA) nanoparticles released 5-FU slowly in the buffer solution, and the cumulative drug release rate increased slowly with time and showed no bursting, good temperature and pH response. That can more accurately target controlled release drugs, reduce the toxicity of normal tissues and organs, improve its positioning and targeting ability.