Photochromic dendrimer diarylethenes with a C-2-connected bisbenzothienylethene core were synthesized; the most notable feature of them is the strong memory effect of cyclizable conformation of the open form when generated from the closed form by visible light irradiation in polycarbonate films.

In this study, an integrated methodology for impact analysis of polycarbonate (PC) product is proposed which incorporates the processing-induced inhomogeneity of yield stress. A previously developed model is extended to predict the inhomogeneous yield stress distribution along the specimen by using the thermal history experienced during injection molding. A strain rate-dependent elastic-plastic...

The mechanisms by which PM(2.5) increases cardiovascular mortality are not fully identified. Autonomic alterations are the current main hypotheses. Our objective was to determine if PM(2.5) induces acute cardiac polarization alterations in healthy Wistar rats. PM(2.5) samples were collected on polycarbonate filters. Solutions containing 10, 20, and 50 microg PM(2.5) were administered by trachea...

This work explores the viability of 3D printed intervertebral lumbar cages based on biocompatible polycarbonate (PC-ISO® material). Several design concepts are proposed for the generation of patient-specific intervertebral lumbar cages. The 3D printed material achieved compressive yield strength of 55 MPa under a specific combination of manufacturing parameters. The literature recommends a refe...

The filler/matrix interface in fiber-reinforced polymer composites is critical in controlling load transfer from the matrix to the fiber, failure mechanisms, and degradation. It is not clear, however, how the mechanisms of load transfer in traditional composites apply to nanofiber-filled polymers. This paper is focused on understanding the reinforcement mechanisms in multiwalled carbon nanotube...

INTRODUCTION Polymer brackets still have some disadvantages because of decreased wear resistance and hardness. The aim of this study was to investigate the mechanical properties of alternative bracket polymers; urethane-dimethacrylate, high-density polyethylene, and an experimental bracket polymer (EBP) consisting of polyethylene and a copolymer were tested. Polycarbonate and polyoxymethylene b...

OBJECTIVE The objective this work was to assess the friction coefficient between brackets and wires of different materials under conditions simulating the oral environment. MATERIAL AND METHODS Stainless steel (SS) and titanium-molybdenum alloy (TMA) wires of 0.019x0.025-in diameter (American Orthodontics) and polycarbonate bracket (American Orthodontics), ceramic bracket (American Orthodonti...

Isentropic stress reverberations are used to obtain multiple Hugoniot states from a single plate impact experiment using a layered plate geometry, where a low impedance inner layer is embedded within a high impedance bulk structure. The mathematical framework used in this technique uses the classical Rankine-Hugoniot equations in the method of impedance matching, where the bulk material is requ...

The widespread application of thermoplastic polymers in different aspects of industries has motivated researchers and companies to improve and upgrade their forming, joining and assembling processes to overcome their limitations. One of the newest joining methods of thermoplastics is friction stir welding which is based on frictional heat generated through contact between a rotating tool and th...

A polycarbonate-based nanohybrid has been created containing 1 wt% of Bentone 2010, an organically modified montmorillonite. A micro-section on the nanohybrid obtained using focused ion beam (FIB) and field emission scanning electron microscopy (FESEM) was employed to observe the orientation of the nanoclay inside a polycarbonate (PC) matrix in the cross-section FIB-milled face. A micro-scratch...