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3D printed carbon fiber reinforced composites (CFRP) have shown great potential in lightweight application. Here, we report a prepreg carbon fiber reinforced polyamide composite by fused filament fabrication 3D printing process. The influence of layer thickness and carbon fiber layers on mechanical properties of 3D printed parts was well studied. With the incorporation of prepreg carbon fibers, the value of tension and flexural strengths of 3D printed CFRP parts could achieve 2.7 and 13.6 times compared to neat polyamide, respectively. Result illustrates that with the prepreg process the carbon fiber have good interface bonding strength with neat polyimide. This work could also be used for more 3D printing composite systems.

A series of aggregation-induced emission (AIE) active polysiloxanes (P7-1~P7-2, P29-1~P29-6) were prepared through hydrosilylation between polymethylhydrosiloxane (PMHS, DP=7 or 29) and AIE-active vinyl monomer 1-(4'-allyloxy-biphenyl)-2,5-diphenyl pyrrole (M-TPP), or with optical active monomer cholesteryl allyloxy ether (M-Chol*). Monomer M-TPP and all of the polymers exhibits aggeragation-induced emission enhancement properties. The fluorescence intensity of M-TPP in THF/H2O mixtures increases when the water fraction is higher than 60%, while is over 20% for polysiloxanes, which mainly because the entanglement of the flexible polysiloxane main-chain can restrict the molecular motion of triphenylpyrrole (TPP) derivates and induce the increasing of the fluorescence intensity. Moreover, the maximum relative fluorescence intensity (I/I0) is equal to 4 for M-TPP and 1.4~4.9 for polysiloxanes, and the grafted degree of the TPP derivative has effect on the AIE properties of polymers. The specific optical rotations of the chiral polymers increase with increasing the content of chiral cholesteryl ether moieties. All the target polymers possess good thermal stabilities and their decomposition points (Td) are greater than 320°C.

Supplemental material, Supplementary_Material-revised for Acid-induced intermolecular [3+2] cycloaddition/oxidation to synthesize polysubstituted benzo[f]isoindole-4,9-diones by Zhang-qi Lin, Chao-dong Li, Yu-jin Li, Yong-jian Zhang, Zi-chun Zhou, Qing Ye and Jian-rong Gao in Journal of Chemical Research

Ion-exchange polymer-metal composite (IPMC) is a new electroactive material. It has large deformation and high force weight ratio in the presence of low voltage (

We elaborate relevant theories of farmers’ relational network, including the Differential Model of Association, the Strength of Weak Tie, Strong Tie Strength, and Favor and Face. The farmers’ relational network in the Differential Model of Association can be divided into three layers: strong tie, weak tie and irrelative relationship according to theory of Granovetter. These three layers have deep influence on opportunity selection during undertaking, financing and enterprise development. With rational knowledge of these layers, farmers may exploit undertaking resources. On the basis of this, we made detailed analysis on farmers’ selection of relations in the opportunity selection, financing and enterprise development stages.