Design And Synthesis Of Photo-sensitive Amphiphilic Block Copolymer And Branched Polymer

In this paper, there are two parts, the main contents of the first part as follow: design and synthesis of four coumarin compounds with different substituent groups which were characterized by UV and FL spectra. It was found that using epichlorohydrin as bridged unit, the aromatic tertiary amine(ATA) was introduced to prepare the highly photo-sensitive coumarin compound CBAE. The introduced ATA can enhance the absorption between 260~400 nm and accelerate the photo-dimerization of coumarin unit. The spot UV irradiation experiments showed that, after being bridged with ATA, the coumarin CBAE would gain a highly photo-dimerization with a high slope of 6.47 in the uniform photo-reaction, and a short time of 29 s to gain 80% photo-dimerization. Then, we used the aromatic tertiary amine-containing coumarin compound(CBAE) react withα-Bromoisobutyryl bromide to synthesize CBAEBr which is initiator of atom transfer radical polymerization(ATRP). Coumarin-containing photo-sensitive block copolymer(C-PS-b-PtBA) was synthesized by ATRP, according to the hydrolysis of C-PS-b-PtBA, we synthesize photo-sensitive amphiphilic block copolymer(C-PS-b-PAA), which were characterized by UV spectra. It was found that photo-sensitive copolymer C-PS-b-PAA solution in DMSO can be photo-dimerized under UV irradiation(>300 nm). After UV irradiation C-PS-b-PAA 100 s, to gain 54% photo-dimerization.In the second part, the sodium thiolsurfuric-containing Styrene monomer(StCS) was designed and synthesized, which can be effectively deprotected to release active SH transfer center in some condition. Using the monomer as branched monomer(StCS) as AB monomer together with 2-hydroxyethyl methacrylate(HEMA) and AIBN to prepare water soluble hyperbranched poly(2-hydroxyethyl methacrylate)(BPHEMA) in DMSO solvent by free radical polymerization, while a mercapto chain-transfer hyperbranched polymerization can be set-up. The hyperbranched polymer were characterized by GPC, 1H NMR and DSC analysis. It was found that the molecular weight (Mw) of HBPHEMA increased exponentially with the increasing dosage of AB monomer, while the glass transient temperature (Tg) decreased and solubility in water increased. Which meaned that through the copolymerization of AB monomer and HEMA, the PHEMA could be hyperbranched.