TY  - JOUR
A1  - Chen, Ye
A1  - Song, Qilei
A1  - Zhao, Junpeng
A1  - Gong, Xiangjun
A1  - Schlaad, Helmut
A1  - Zhang, Guangzhao
T1  - Betulin-Constituted multiblock amphiphiles for broad-spectrum protein resistance
JF  - ACS applied materials & interfaces
N2  - Multiblock-like amphiphilic polyurethanes constituted by poly(ethylene oxide) and biosourced betulin are designed for antifouling and synthesized by a convenient organocatalytic route comprising tandem chain-growth and step-growth polymerizations. The doping density of betulin (D-B) in the polymer chain structure is readily varied by a mixed-initiator strategy. The spin-coated polymer films exhibit unique nanophase separation and protein resistance behaviors. Higher D-B leads to enhanced surface hydrophobicity and, unexpectedly, improved protein resistance. It is found that the surface holds molecular-level heterogeneity when D-B is substantially high due to restricted phase separation; therefore, broad-spectrum protein resistance is achieved despite considerable surface hydrophobicity. As D-B decreases, the distance between adjacent betulin units increases so that hydrophobic nanodomains are formed, which provide enough landing areas for relatively small-sized proteins to adsorb on the surface.
KW  - amphiphilic surface
KW  - antifouling
KW  - multiblock copolymer
KW  - organocatalytic polymerization
KW  - renewable resource
Y1  - 2018
U6  - https://doi.org/10.1021/acsami.7b16255
SN  - 1944-8244
VL  - 10
IS  - 7
SP  - 6593
EP  - 6600
PB  - American Chemical Society
CY  - Washington
ER  - 
TY  - JOUR
A1  - Hu, Shuangyan
A1  - Zhao, Junpeng
A1  - Zhang, Guangzhao
A1  - Schlaad, Helmut
T1  - Macromolecular architectures through organocatalysis
JF  - Progress in Polymer Science
N2  - In virtue of the rising demand for metal-free polymeric materials, organocatalytic polymerization has emerged and blossomed unprecedentedly in the past 15 years into an appealing research area and a powerful arsenal for polymer synthesis. In addition to the inherent merits as being metal-free, small molecule organocatalysts have also provided opportunities to develop alternative and, in many cases, more expedient synthetic approaches toward macromolecular architectures, that play a crucial role in shaping the properties of the obtained polymers. A majority of preliminary studies exploring for new catalysts, catalytic mechanisms and optimized polymerization conditions are extended to application of the catalytic systems on rational design and controlled synthesis of various macromolecular architectures. Such endeavors are described in this review, categorized by the architectural elements including chain structure (types, sequence and composition of monomeric units constituting the polymer chains), topological structure (the fashion different polymer chains are covalently attached to each other within the macromolecule) and functionality (position and amount of functional groups that endow the entire macromolecule with specific chemical, physico-chemical or biological properties). (C) 2017 Published by Elsevier B.V.
KW  - Organocatalytic polymerization
KW  - Metal-free polymerization
KW  - Macromolecular architecture
KW  - Controlled polymer synthesis
Y1  - 2017
U6  - https://doi.org/10.1016/j.progpolymsci.2017.07.002
SN  - 0079-6700
SN  - 1873-1619
VL  - 74
SP  - 34
EP  - 77
PB  - Elsevier
CY  - Oxford
ER  -