Ring-opening metathesis polymerization of norbornene derivatives for multifunctionalized all-optical photorefractive polymers with a non-conjugated main chain

All-optical non-conjugated multi-functionalized photorefractive polymers via ring-opening metathesis polymerization

Non-conjugated multi-functionalized all-optical photorefractive (PR) polymers were designed and synthesized via ring-opening metathesis polymerization (ROMP) of two monomers using Grubbs II catalyst as an initiator. The polymers were characterized by infrared (IR) spectrum, gel permeation chromatography (GPC), UV-visible spectrum (UV-Vis), differential scanning calorimetry (DSC), thermogravimetry (TG) and so on. The number-average molar mass (Mn) of the polymers is no less than 8.5 × 104 while their glass transition temperatures of 52°C and 45°C are close to the room temperature, which is helpful to the enhancement of PR orientation and the fabrication of PR devices. The polymers have good thermal stability and great solubility in tetrahydrofuran (THF). Without any plasticizer, the transparent optical films can be prepared by solution-casting with THF solution of polymers. Their PR properties at 633 nm were evaluated by two beam coupling (TBC) experiments under zero electric field without prepoling. It is shown that the single-component polymer has obvious all-optical PR behavior.

Fabrications and Applications of Stimulus-Responsive Polymer Films and Patterns on Surfaces: A Review

In the past two decades, we have witnessed significant progress in developing high performance stimuli-responsive polymeric materials. This review focuses on recent developments in the preparation and application of patterned stimuli-responsive polymers, including thermoresponsive layers, pH/ionic-responsive hydrogels, photo-responsive film, magnetically-responsive composites, electroactive composites, and solvent-responsive composites. Many important new applications for stimuli-responsive polymers lie in the field of nano- and micro-fabrication, where stimuli-responsive polymers are being established as important manipulation tools. Some techniques have been developed to selectively position organic molecules and then to obtain well-defined patterned substrates at the micrometer or submicrometer scale. Methods for patterning of stimuli-responsive hydrogels, including photolithography, electron beam lithography, scanning probe writing, and printing techniques (microcontact printing, ink-jet printing) were surveyed. We also surveyed the applications of nanostructured stimuli-responsive hydrogels, such as biotechnology (biological interfaces and purification of biomacromoles), switchable wettability, sensors (optical sensors, biosensors, chemical sensors), and actuators.

Effect of Solution Content ZnO Nanoparticles on Thermal Stability of Polyvinyl Chloride

Today's pipe made of polyvinyl chloride (PVC) is used as basic good in different industries. The thermal stability of the PVC while is filled with ZnO nanoparticles was studied in this paper. This paper show that the stability of the PVC resin mixed with ZnO nanoparticles solution and Sn was better than that of the PVC resin mixed with Sn alone. The UV (ultraviolet)–vis spectra is showed that under certain heat treatment conditions, the PVC samples without ZnO nanoparticles solution embodied relatively high content of the conjugated double bonds with the chain length of about 3–5. However, the content of the conjugated double bond with the chain length of about 6 was greatly increased when the nanoparticles was filled into the PVC resin. This work shows the ZnO nanoparticles could inhibit the thermal degradation process of PVC resin in ionic mechanism.