Triple-transforming gel prepared byβ-cyclodextrin,diphenylamine and lithium chloride in N,N-dimethylacetamide

This paper describes a triple-transforming gel system （gel-sol-gel＇） for the first time, which is a thermo-responsive and multi- component organogel prepared by β-cyclodextrin （β-CD）, diphenylamine （DPA） and lithium chloride （LiCl） in N,N-dimethyla- cetamide （DMAC） in a suitable proportion based on the supramolecular interactions. In the triple-transfomaing gel system, a gel （gel A） could be formed by β-CD, DPA and LiCl in DMAC at room temperature based on stirring, then the gel could transform into a clear solution based on heating, and then the other gel （gel B） can be formed at a relatively high temperature （Tget, the gelation temperature by heating）. The two gel states in the triple-transforming gel system have different microstructures. This gel system was characterized by OM, SEM, IR and theology.

Solid and liquid phase equilibria in mixtures of N, N-dimethylacetamide with chlorinated hydrocarbons

IN refs.[1,2],we studied the solid and liquid phase equilibria in mixtures of tetra-chloromethane with oxygen and nitrogen-containing compounds,intermolecular interactionswith the formation of solid molecular addition compounds.The nitrogen atom linking withthree carbon atoms is a strong electron donor,so is N,N-dimethylacetamide(DMA).

“One stone,two birds”solvent system to fabricate microcrystalline cellulose–Ti_(3)C_(2)T_(x)nanocomposite film as a flexible dielectric and thermally conductive material

A strategy for fabricating microcrystalline cellulose–Ti_(3)C_(2)T_(x)(MCC–MXene)nanocomposite films with high relative permittivity,high thermal conductivity,and excellent mechanical properties was developed.The MCC–MXene nanocomposite film was fabricated by casting a solution containing N,N-dimethylacetamide/lithium chloride(DMAc/LiCl)-soluble MCC and DMAcdispersible MXene nanosheets,followed by humidity control drying.The MXene nanosheets greatly enhanced the permittivity of the nanocomposite films owing to interfacial polarization.Thus,the nanocomposite film with 20 wt.%MXene content achieved a desirable permittivity of 71.4 at 102 Hz(a 770%improvement against that of neat cellulose),while the dielectric loss only increased by 1.8 times(from 0.39 to 0.70).The obtained nanocomposite films with 20 wt.%and 30 wt.%MXene exhibited remarkable in-plane thermal conductivities of 8.523 and 9.668 W∙m^(−1)∙K^(−1),respectively,owing to the uniform dispersion and selfalignment of the MXene layered structure.Additionally,the uniformly dispersed MXene nanosheets in the MCC network with interfacial interaction(hydrogen bonding)and mechanical entanglement endowed the nanocomposite films with excellent mechanical properties and flexibility.Furthermore,the thermal stability,water resistance,and antibacterial properties of the nanocomposite films were effectively improved with the introduction of MXene.Moreover,using DMAc/LiCl as the solvent system not only improves the compatibility between MCC and MXene but also avoids the problem of easy oxidation of MXene in aqueous systems.With the high stability of the MCC–MXene solution and enhanced properties of the MCC–MXene films,the proposed strategy manifests great potential for fabricating natural biomass-based dielectric materials.

C–H Arylation using acyl thiourea ligands: Applications in the synthesis of 3,6-diaryl-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazoles

Synthesis of a series of new 3,6-diaryl-[1,2,4]triazolo[3,4-b] [1,3,4]thiadiazoles（5a-o） was achieved by phophine free, C-H arylative cross-coupling of 6-aryl-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazoles（4a-o）with suitably substituted iodoanilines using 1-（2-naphthoyl）-3-（4-bromophenyl）thiourea as a ligand.The requisite triazolothiadiazoles（4a-o） were obtained by the condensation of 4-amino-1,2,4-triazole-3-thiol（3） with suitably substituted aromatic acids in the presence of phosphoryl chloride.