We synthesized four diphenylquinoxaline derivatives(SQs) with phenyl-thioether units, which combine photo-cleavable and hydrogen-abstracting groups in one molecule. The photochemistry and photopolymerization of SQs were investigated. SQs possess suitable UV-vis absorption in the range of 350-400 nm with high extinction coefficients. UV-vis and HPLC-MS spectra revealed that C–S bond in phenyl-thioether group of SQs can be broken by irradiation of UV-light. Photolysis and photopolymerization experiments showed that SQs can be used as photo-cleavable photointiators,their photoinitiating efficiency can be enhanced by hydrogen donor. As photo-cleavable photoinitiators,SQs could initiate hexamethylene diacrylate(HDDA) very efficiently with the double bond conversion(DBC) of 80%. In the presence of ethyl-4-(dimethylamino) benzoate(EDB) as coinitiator, photoinitiator systems initiated photopolymerization of commercial acrylate monomers with higher double bond conversion than 90%. These characteristics make SQs potential photoinitiators in photo-curing field.
This work reports a SO2 derivative-detecting and colorful hyperbranched polymeric ionic liquid (HBPIL) vesicle through aqueous self-assembly. By a simple anion-exchange, we achieved the combination of functional small-molecule probe of acid fuchsin with HBPILs. The obtained HBPIL vesicle displayed ultraviolet absorption at 544 nm, and was used as a novel SO2 derivative sensor with high sensitivity and visualization. Due to the functional ion pairs enriching on the surface, the SO32 detection limit of the HBPILs vesicles was as low as 0.138 gmol/L, which was about 1.5 orders of magnitude lower than that of acid fuchsin.
Zhi-lin HouTong HuangCai-yun CaiTahir Resheed于春阳Yong-feng ZhouDe-yue Yan
We reported a facile and bio-inspired strategy for obtaining antireflective (AR) coating through polymerization-induced self-wrinkling. Upon irradiation of light, the complex wrinkle micro-patterns with different morphologies were generated spontaneously on the surface of coating during photo-cross- linking, which enables the photo-curing coating can decrease reflection. The resulting photo-curing coating exhibits a high transmittance over 90% and low reflection below 5% ~ 8%, with an efficiency anti- reflection of 4% ~ 7%; compared to the flat blank coating. The successful application of these AR coatings with wrinkles pattern to encapsulate the thin film solar cells results in appreciable photovoltaic performance improvement of more than 4% ~ 8%, which benefits from the decrease of the light reflection and increase of optical paths in the photoactive layer by the introduction of wrinkling pattern. Furthermore, the efficiency improvements of the solar cells are more obvious, with a remarkable increase of 8.5%, at oblique light incident angle than that with vertical light incident angle
By controlling the feed ratio of CMS/styrene and the polymerization time, a series of hyperbranched copolystyrenes(HBCPS) were synthesized with comparable weight-averaged molecular weights(Mw) but different degree of branching(DB) through atom transfer radical self-condensing vinyl copolymerization(ATR-SCVCP) with Cu Br/2,2?-bipyridyl as the catalyst. The resulting HBCPS samples were used to investigate the effect of branching architecture on their glass transition behavior. With the DB increased, the glass transition temperatures(Tg) of HBCPS samples measured by DMA and DSC both decreased. Their spin-lattice relaxation times(1H T1r) of protons displayed the same downtrend with increasing DB. Besides, a correlation between the Tgs and the DB was well established by all-atom molecular dynamics(MD) simulations. The values of MD-determined Tgs are little higher than the corresponding experimental ones. However, the dependence of Tgs on DB is in good agreement with the experimental results, i.e., Tg decreases both in experiments and simulations with increasing DB.