Performance of bitumen coating sheet using biomass pyrolysis oil.

The "green" production of bitumen has raised increasing interest in recent years to reduce the environmental, energy-related and petro-based concerns. Bio-oil, prepared by biomass pyrolysis, can be used as a substitute for petro-based bitumen in bitumen or bitumen-based coatings, for its similar properties of good adhesion and anti-corrosion characteristics as bitumen. Although biomass is a renewable and widespread chemical resource, its high-valued utilization is still difficult. Several studies have qualitatively demonstrated the use of bio-bitumen in practical applications. The present study investigates that adding some bio-oil to traditional bitumen to form a bio-bitumen could help improve the properties of traditional bitumen. Bio-bitumen was prepared from biomass pyrolysis oil and applied to self-adhesive and doped hot-melt sheets. Results of physical properties demonstrate that bio-bitumen is a potential substitute in bitumen coating sheet.Implications: This paper is intended to verify the effect of pyrolyzed bio-oil from wheat straw on the performance of bitumen, as well as the feasibility of application in the coating sheet. Up to now, the research on bio-bitumen is mainly in pavement bitumen. In the present research, bio-bitumen was applied to the coating sheet in different proportions. Interestingly, the prepared coating sheet exhibited higher adhesion. Other performances, such as temperature stability, mechanical strength and temperature flexibility of coating sheet showed improvement in the presence of bio-oil, which indicated the suitability of bio-oil in coating sheet bitumen.

Switchable Reversible Addition-Fragmentation Chain Transfer (RAFT) Polymerization with the Assistance of Azobenzenes.

Modulating controlled radical polymerization is an interesting and important issue. Herein, modulating RAFT polymerization employing photosensitive azobenzenes is achieved. In the presence of azobenzenes and with visible light off, RAFT polymerization runs smoothly and follows a pseudo-first-order kinetics. In contrast, with light on, RAFT polymerization is greatly decelerated or quenched depending on the type and concentration of azobenzenes. Switchable RAFT polymerization of different (meth)acrylate monomers alternatively with light off and on is demonstrated. A mechanism of photoregulating RAFT polymerization involving radical quenching by azobenzenes is proposed.

Synthesis of Multicompartment Nanoparticles of ABC Miktoarm Star Polymers by Seeded RAFT Dispersion Polymerization.

Polymeric multicompartment nanoparticles (MCNs) of µ-ABC miktoarm star polymers composed of poly(N,N-dimethylacrylamide) (PDMA), poly(butyl methacrylate) (PBMA), and polystyrene (PS) were synthesized by Cu(I)-catalyzed click reaction and seeded RAFT dispersion polymerization. The synthesized MCNs have a solvophobic PBMA core with separate segregated PS microdomains and a solvophilic PDMA corona. The size and/or morphology of MCNs are correlative to the length of PDMA, PBMA, and PS segments. Ascribed to the characteristic structure, MCNs of µ-DBS can decrease interfacial tension in n-hexane/water, which is much superior to linear diblock copolymer nanoassemblies.