Hu, Jin; Mo, Ruibin; Jiang, Xiang; Sheng, Xinxin; Zhang, Xinya
Towards mechanical robust yet self-healing polyurethane elastomers via combination of dynamic main chain and dangling quadruple hydrogen bonds
One of the greatest challenges of robust self-healing materials is the confliction between high chain mobility for self-healing and a stable structure for mechanical strength. Herein, dangling 2-ureido-4-pyrimidione (UPy)-functionalized side groups were introduced into the hard segments of thermoplastic polyurethane (TPU) elastomers, where embedded the dynamic disulfide bonds in the…
Chirality Transfer in Coassembled Organogels Enabling Wide-Range Naked-Eye Enantiodifferentiation
Yue, Bingbing; Yin, Liyuan; Zhao, Wandong; Jia, Xiaoyong; Zhu, Mingjie; Wu, Bin; Wu, Si; Zhu, Liangliang
Enantiodifferentiation is crucial in organic chemistry, pharmacochemistry, material chemistry, and life science. However, it remains tremendously challenging to achieve a broad enantioselectivity to different types of chiral substrates via a single-material design. Here, we report a coassembled organogel strategy with chirality transfer to make an enantioselective generality possible. This
Effects of Hard Segment of Polyurethane with Disulfide Bonds on Shape Memory and Self-Healing Ability
Ha, Yu-Mi; Seo, Hae Cheon; Kim, Young-O; Khil, Myung-Seob; Cho, Jae Whan; Lee, Jae-Suk; Jung, Yong Chae
Self-healing polyurethane with disulfide bonds was synthesized using polycarbonate diol as a soft segment, and methylene diphenyl diisocyanate and 2-hydroxyethyl disulfide as a hard segment. Well-developed phase separation as the hard segments increased was confirmed by Fourier transform infrared spectra. The X-ray diffraction data showed that the crystallinity of the…
Periodic Polyethylene Sulfonates from Polyesterification: Bulk and Nanoparticle Morphologies and Ionic Conductivities
Rank, Christina; Yan, Lu; Mecking, Stefan; Winey, Karen I.
A series of polyethylene-like ionomers with periodic sulfonate groups were synthesized by polyesterification of octatetracontane-1,48-diol and tetrabutylammonium dimethyl sulfosuccinate. Optional cation exchange in aqueous dispersions replaced the NBu4+ counterions for Na+ or Cs+. The defined periodic microstructure of the polymers leads to the formation of layered structures in bulk and…
Moebius strips of chiral block copolymers
Geng, Zhen; Xiong, Bijin; Wang, Liquan; Wang, Ke; Ren, Min; Zhang, Lianbin; Zhu, Jintao; Yang, Zhenzhong
The Moebius topology (twisted, single-sided strip) is intriguing because of its structural elegance and distinct properties. Here we report the generation of block copolymer Moebius strips via a fast self-assembly of chiral block copolymer polystyrene-block-poly(D-lactide acid) (PS-b-PDLA) in tetrahydrofuran/water mixed solvents. The Moebius strip is formed by morphological evolution from…
Solvent-non-solvent rapid-injection for preparing nanostructured materials from micelles to hydrogels
Lang, Chao; LaNasa, Jacob A.; Utomo, Nyalaliska; Xu, Yifan; Nelson, Melissa J.; Song, Woochul; Hickner, Michael A.; Colby, Ralph H.; Kumar, Manish; Hickey, Robert J.
Due to their distinctive molecular architecture, ABA triblock copolymers will undergo specific self-assembly processes into various nanostructures upon introduction into a B-block selective solvent. Although much of the focus in ABA triblock copolymer self-assembly has been on equilibrium nanostructures, little attention has been paid to the guiding principles of nanostructure…
Transition Pathway between Gyroid and Cylindrical Morphology in Linear Triblock Terpolymer Thin Films
Guliyeva, Aynur; Vayer, Marylène; Warmont, Fabienne; Takano, Atsushi; Matsushita, Yushu; Sinturel, Christophe
A new transition between alternating gyroid (GA) structure and cylindrical morphology was observed in thin films for a poly(isoprene-block-styrene-block-(2-vinylpyridine)) (ISP) triblock terpolymer (I/S/P volume fraction = 0.20:0.66:0.14) exhibiting in bulk a Q214 (space group I4132) morphology. Thin films were organized using solvent vapor annealing (SVA) and characterized by atomic force
The influence of pH, protein concentration and calcium ratio on the formation and structure of nanotubes from partially hydrolyzed bovine ?-lactalbumin
Geng, XiaoLu; Kirkensgaard, Jacob Judas Kain; Arleth, Lise; Otte, Jeanette; Ipsen, Richard
Formation of nanotubes from partially hydrolysed ?-lactalbumin (?-La) was investigated at five pH values, two concentrations of ?-La and two calcium levels. Nanotubes were formed under almost all combinations of the investigated factors, and for the first time the formation of nanotubes at low pH (4.0) and low protein concentration…
Polymorphic states and phase transitions in a comb-like polymer having a rigid polyester backbone and flexible side chains
Danke, Varun; Gupta, Gaurav; Huth, Heiko; Schawe, Jürgen E. K.; Beiner, Mario
Structure formation in an alkoxylated polyester having rigid backbone and flexible side chains composed of 10 alkyl carbons per side chain is studied using X-ray diffraction, conventional DSC and flash DSC techniques. Two crystalline states-modification B and modification A are observed with their occurrence depending on the thermal treatment. Additionally,…
Power Law Relaxations in Lamellae Forming Brush Block Copolymers with Asymmetric Molecular Shape
Yavitt, Benjamin M.; Fei, Hua-Feng; Kopanati, Gayathri N.; Winter, H. Henning; Watkins, James J.
We report the linear viscoelasticity of densely grafted poly(styrene)-block-poly(ethylene oxide) (PS-b-PEO) diblock bottlebrush block copolymers (dbBB) of equal mass fraction over a wide range of backbone degree of polymerization (Nbb = 21119). The difference in side chain length (PS Mn = 2.9 kg/mol, PEO Mn = 5 kg/mol) produces an…