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A series of hydroxyl-terminated polyethylenes (HTPE) bearing various functional side groups (e.g. carboxyl, ester and butane groups) were synthesized by the combination of ring-opening metathesis polymerization (ROMP) and visible light photocatalytic thiol-ene reaction. The products are named as α, ω-dihydroxyl-poly[(propionyloxythio)methinetrimethylene] (HTPEcarboxyl), α, ω-dihydroxyl-poly[(methylpropionatethio) methinetrimethylene] (HTPEester) and α, ω-dihydroxyl-poly[(butylthio) methinetrimethylene] (HTPEbutane), respectively. The investigation of ROMP indicated that the molecular weight of resultant hydroxyl-terminated polybutadiene (HTPB) can be tailored by varying the feed ratios of monomer to chain transfer agent (CTA). The exploration of the photocatalytic thiol-ene reaction between HTPB precursor and methyl 3-mercaptopropionate revealed that blue light as well as oxygen accelerated the reaction. 1H-NMR and 13C-NMR results verified all the double bonds in HTPB can be modified, and the main chain of resultant polymer can be considered as polyethylene. Subsequently, relationship between the structure of side groups and the thermal properties of functional PEs was studied. And the results suggested that the Tg was in the order of HTPEbutaneestercarboxyl. Greater interaction between side groups resulted in higher Tg. Moreover, all the functional PE samples exhibited poor thermostability as compared to HTPB. Finally, the promising applications for functional PEs were explored. HTPEcarboxyl can be utilized as a smart material with pH-responsive properties due to its pH-dependent ionization of carboxyl side groups. HTPEbutane can be employed as a macro-initiator for building the triblock copolymer due to the presence of active hydroxyl end groups. HTPEester can serve as a plasticizer for PVC which can enhance the ductility of PVC without obviously sacrificing strength. [ABSTRACT FROM AUTHOR]

Based on local operations and classical communication, a tripartite quantum operation sharing (QOS) scheme is proposed by utilizing a genuine five-qubit entangled state as quantum channel. The present scheme has such prominent features as the arbitrariness of the concerned operation and the determinacy of sharing successfully as well as the constancy of entanglement resource. Besides, its intrinsic efficiency has come up to 10 % , higher than most previous QOS schemes. More importantly, in terms of complexity, the operations which are necessary to accomplish the present QOS task as a whole are extremely simplistic. In addition, our scheme is feasible with the current experimental techniques. [ABSTRACT FROM AUTHOR]

The controlled secondary self-assembly of amphiphilic molecules in solution is theoretically and practically significant in amphiphilic molecular applications. An amphiphilic β-cyclodextrin (β-CD) dimer, namely LA-(CD)2, has been synthesized, wherein one lithocholic acid (LA) unit is hydrophobic and two β-CD units are hydrophilic. In an aqueous solution at room temperature, LA-(CD)2 self-assembles into spherical micelles without ultrasonication. The primary micelles dissociates and then secondarily form self-assemblies with branched structures under ultrasonication. The branched aggregates revert to primary micelles at high temperature. The ultrasound-driven secondary self-assembly is confirmed by transmission electron microscopy, dynamic light scattering, 1H NMR spectroscopy, and Cu2+-responsive experiments. Furthermore, 2D NOESY NMR and UV/Vis spectroscopy results indicate that the formation of the primary micelles is driven by hydrophilic-hydrophobic interactions, whereas host-guest interactions promote the formation of the secondary assemblies. Additionally, ultrasonication is shown to be able to effectively destroy the primary hydrophilic-hydrophobic balances while enhancing the host-guest interaction between the LA and β-CD moieties at room temperature. [ABSTRACT FROM AUTHOR]