Science China-Materials
·
2021
·Vol. 64
·期 8
·2008-2016
·
IF 8.273
Wen Xin,Lin Chensheng,Luo Min,Fan Huixin,Chen Kaichuang,Ye Ning
[PO 4 ] 3− possesses small microscopic second-order susceptibility and polarizability anisotropy, which inherently result in weak second-harmonic generation (SHG) and small birefringence. Herein, a new noncentrosymmetric phosphate, [C(NH 2 ) 3 ] 3 PO 4 ·2H 2 O, was successfully designed and synthesized by a solution evaporation method. [C(NH 2 ) 3 ] 3 PO 4 ·2H 2 O without metal ions is composed of planar conjugated guanidine cations and PO 4 tetrahedrons, which are connected by hydrogen bonds, forming a three-dimensional network. Physical property measurements indicate that the title compound displays an SHG response of 1.5 × KH 2 PO 4 (KDP) and a larger birefringence (0.055@546.1 nm) compared with most reported ultraviolet nonlinear optical phosphates. Furthermore, first-principles calculations reveal that the π-conjugated planar [C(NH 2 ) 3 ] + cations and [PO 4 ] 3− groups are responsible for its excellent linear and NLO properties.
研究领域:
材料科学
·
光学工程
·
无机化学
·
晶体工程
·
非线性光学
✓ 已验证
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2015
·Vol. 17
·期 38
·25525-25535
·
IF 4.493
Yuanyuan Zhou,Hui Tang,Peiyi Wu
Thermo-dynamic volume phase transition mechanisms of poly[oligo(ethylene glycol)methacrylate] (POEGMA) based microgels with poly(ionic liquid) (PIL) cross-linking moieties are investigated in detail on the basis of temperature-dependent Fourier transform infrared (FTIR) spectroscopy. The original FTIR data are further analysed by two-dimensional correlation spectroscopy (2Dcos) with the perturbation correlation moving window (PCMW) technique. It is observed that the content of hydrophilic PIL cross-linking structure strongly affects the temperature induced volume phase transition mechanism of microgels in which the less cross-linked microgel exhibits a sharp volume phase transition process while the highly cross-linked microgel presents a broad transition behavior. Peculiarly, the dehydration of C–H groups acts as the driving force for the whole phase transition process within the less cross-linked microgel network and cooperative response of chemical groups is identified. It is deduced that the hydrophilic PIL moieties develop polymer–water–polymer interactions with CO groups as CO⋯D2O–PIL hydrogen bonds emerge in the less cross-linked system. As regards the highly cross-linked microgel system, the phase transition process is driven by the disruption of hydrogen bonds between CO groups and water molecules while the response of C–H groups becomes insensitive. PIL moieties passively dehydrate following the dehydration of C–H groups on oligo(ethylene glycol) side chains and no hydrogen bond between CO group and IL–D2O association appears during the phase transition process.
研究领域:
高分子科学
·
软物质物理
·
生物材料
·
药物递送
·
智能响应材料
✓ 已验证
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 36
·22485-22491
·
IF 3.108
Hailiang Zhao,Shanshan Tang,Qun Zhang,Lin Du
The weak intermolecular interaction between 2,2,2-trifluoroethanol (TFE) and 3-chloro-2-methyl-1-propene (CMP) has been investigated by gas phase FTIR spectroscopy and DFT calculations. CMP offers two hydrogen bond docking sites to the hydrogen bond donor: the chlorine atom (O–H⋯Cl) and the CC π electron system (O–H⋯π). DFT calculations suggest that MeOH approaches CMP in five different orientations. The structural, energetic, and spectroscopic parameters of the most stable structures in each orientation were studied, and their binding energies range from −25.5 to −19.5 kJ mol−1. The docking to the π system is at least 1 kJ mol−1 more favored than the docking to the chlorine atom. The equilibrium constant for complexation (2.3 × 10−2) was determined from the experimental and calculated intensity of the OH-stretching transition. The Gibbs free energy of formation was found to be 9.3 kJ mol−1. The nature of the non-covalent interaction was analyzed with the atoms in molecules (AIM) method.
研究领域:
物理化学
·
结构化学
·
分子光谱学
·
量子化学计算
·
分子间相互作用
✓ 已验证
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS
·
2018
·Vol. 56
·期 19
·1281-1286
·
IF 2.499
Yan Jie Wang,Chen Yu Li,Zhi Jian Wang,Yiping Zhao,Li Chen,Zi Liang Wu,Qiang Zheng
Development of tough hydrogels has greatly expanded their applications as load-bearing materials. However, the elastic modulus of tough hydrogels is usually lower than 1 MPa. It remains a challenge to design tough hydrogels with high modulus. We report here a series of tough double-network (DN) hydrogels with ultrahigh elastic modulus (up to 200 MPa) by forming robust hydrogen bonds between the first poly(acrylic acid) network and the second poly( N -isopropyl acrylamide) network. The dense cooperative hydrogen bonds greatly reduce the segmental mobility and thus improve the rigidity of gel matrix. Owing to the dynamic nature of hydrogen bonds, the modulus of hydrogels is strongly influenced by temperature and pH, affording the gels shape memory property. The strategy by forming robust noncovalent bonds between interpenetrating networks should be applicable to other systems for designing tough and versatile hydrogels with diverse promising applications. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018 , 56 , 1281–1286
研究领域:
高分子物理
·
生物材料
·
软物质科学
·
智能响应材料
·
组织工程
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2016
·
IF 4.836
Man Zhang,Rui Wang,Zhenqiang Shi,Xuelian Huang,Weifeng Zhao,Changsheng Zhao
A novel family of multi-responsive, tough, and reversible hydrogels were prepared by the combination of dipole-dipole interaction, hydrogen bonding interaction and slightly chemical cross-linking, using monomers of acrylonitrile, sodium allylsulfonate and itaconic acid. Reversible gel-sol transition was achieved by the flexible conversion of the dipole-dipole interactions between acrylonitrile-acrylonitrile and acrylonitrile-sodium thiocyanate, and the hydrogels could freely form desired shapes. The dipole-dipole and hydrogen bonding interactions improved the mechanical strength of the hydrogels with a compressive stress of 2.38 MPa. Meanwhile, the hydrogels sustained cyclic compressive tests with 60% strain, and exhibited excellent elastic property. The hydrogels were sensitive to pH and ionic strength, and could keep their perfect spherical structures without any obvious cracks even after immersing in strong ionic strength (or pH) solution for several reversible cycles. Furthermore, the hydrogels were recycled for environmental pollution remediation, and showed great potential to be applied in water treatments and other related fields.
研究领域:
高分子材料科学
·
生物医学工程
·
环境修复
·
功能水凝胶
·
智能响应材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）