Synthesis and Polymerization Kinetics of Rigid Tricyanate Ester

A new rigid tricyanate ester consisting of seven conjugated aromatic units is synthesized, and its structure is confirmed by X-ray analysis. This ester undergoes thermally stimulated polymerization in a liquid state. Conventional and temperature-modulated differential scanning calorimetry techniques are employed to study the polymerization kinetics. A transition of polymerization from a kinetic- to a diffusion-controlled regime is detected. Kinetic analysis is performed by combining isoconversional and model-based computations. It demonstrates that polymerization in the kinetically controlled regime of the present monomer can be described as a quasi-single-step, auto-catalytic, process. The diffusion contribution is parameterized by the Fournier model. Kinetic analysis is complemented by characterization of thermal properties of the corresponding polymerization product by means of thermogravimetric and thermomechanical analyses. Overall, the obtained experimental results are consistent with our hypothesis about the relation between the rigidity and functionality of the cyanate ester monomer, on the one hand, and its reactivity and glass transition temperature of the corresponding polymer, on the other hand.

Fibrous membranes electrospun from the suspension polymerization product of styrene and butyl acrylate for oil–water separation

Fibrous membranes electrospun from the copolymer of styrene and butyl acrylate could separate oil from water due to their excellent hydrophobicity.

Synthesis of Poly L-Glutamate Initiated by Triethanolamine

With L-glutamic acid as raw materials, N-carboxy-L-glutamic acid-benzyl-anhydride (BLG-NCA) was synthesized by triethanolamine. With triethanolamine as the initiator in the anhydrous dichloromethane, ring-opening polymerization of BLG-NCA was initiated, poly-l-glutamic acid benzyl ester was obtained. The amount of initiators, molar ratio of monomer/initiators, reaction temperature and reaction time to the effect of poly-l-glutamic acid benzyl ester in the ring-opening polymerization of BLG-NCA were studied. At last, poly L-glutamate was got, after the debenzylation in HBr solution. Through infrared spectroscopy, Ubbelohde viscometer, 1H NMR spectra, polymerization product was characterized and analysized. Results showed that in dichloromethane, ring-opening polymerization of BLG-NCA could be initiated by triethanolamine.

High power TEA-CO2 laser induced polymerization of ethylene

A 100-MW double-discharged TEA-CO2 laser was used to induce the polymerization of ethylene gas at pressures ranging from 250 to 900 psi at room temperature. The polymerization product was mainly tetradecane (CH3(CH2)12CH3) (∼80%) and octadecane (CH3(CH2)16CH3) (∼20%).