Polymer blend

About: Polymer blend is a research topic. Over the lifetime, 18474 publications have been published within this topic receiving 437183 citations. The topic is also known as: polymer mixture & Polymerblend 或者 Polyblend.

Supercritical fluids and polymers – The year in review – 2014

Abstract: A critical overview of publications on applications of supercritical fluids in polymer formation, modification and processing is presented. The review is focused on publications that appeared in 2014 only with the intent of providing an in-depth look at the activity in the most recent year to gain insights on the more recent trends and opportunities. The articles have been grouped under ten different application areas which include (1) polymer solutions and phase behavior, (2) polymerizations, (3) particle formation/micronization/drug delivery systems, (4) films, (5) fibers, (6) membranes, (7) nanocomposites, (8) porous materials – foams/scaffolds, (9) organogels, and (10) lignocellulosic polymers. In each category, articles are discussed under specific polymer or polymer type to better highlight those polymers that are receiving the greater level of attention. In 2014, more polymers were explored for their foamability, and for generation of nanocomposites. Poly(ɛ-caprolactone), poly(lactic acid) and poly(lactide-co-glycolide) were the most frequently investigated polymers for their porous matrix formation, or particle formation features using supercritical carbon dioxide because of their biomedical significance as biodegradable platforms for tissue engineering scaffolds and drug delivery devices. Poly(ethylene oxide), poly(lactic acid), and poly(methyl methacrylate) were the polymers that were explored in multiple application areas. Based on the close examination of these publications, the review provides specific observations on the advances that are made toward improved understanding of the factors that affect the miscibility of polymers in carbon dioxide, and for further understanding of the synergistic or other effects of components in polymer blends and composites, including the consequences of the presence of crystalline versus amorphous domains and morphological differences, or the consequences of the presence of nanofillers in different applications. New perspectives that are emerging in each application area are presented.

Polymer mixture having aromatic polycarbonate styrene I containing copolymer and/or graft polymer and a flame-retardant, articles formed therefrom

Abstract: The invention relates to a polymer mixture which comprises an aromatic polycarbonate, a styrene-containing copolymer and/or a styrene-containing graft polymer and a flame-retardant. It has been found that the use of a certain type of flame-retardants, namely oligomeric phosphates leads to a polymer mixture having improved properties. In particular to a polymer mixture having a good combination of flame retardancy, non-juicing characteristics of the flame retardant, good plastifying effect and good heat resistance.

Designing Multiple-Shape Memory Polymers with Miscible Polymer Blends: Evidence and Origins of a Triple-Shape Memory Effect for Miscible PLLA/PMMA Blends

Abstract: Shape memory properties of polymers represent one of the most expanding fields in polymer science related to numerous smart applications. Recently, multiple-shape memory polymers (multiple-SMPs) have attracted significant attention and can be achieved with complex polymer architectures. Here, miscible PLLA/PMMA blends with broad glass transitions are investigated as an alternative platform to design multiple-SMPs. Dual-shape memory experiments were first conducted at different stretching temperatures to identify the so-called “temperature memory effect”. The switch temperature of the symmetric 50% PLLA/50% PMMA blend smoothly shifted from 70 to 90 °C for stretching temperatures increasing from 65 to 94 °C, attesting for a significant “temperature memory effect”. Asymmetric formulations with 30% and 80% PMMA also present a “temperature memory effect”, but the symmetric blend clearly appeared as the most efficient formulation for multiple-shape memory applications. A programming step designed with two succe...

Highly efficient polymer light-emitting devices using ambipolar phosphorescent polymers

Abstract: We report on highly efficient polymer light-emitting devices (PLEDs) achieved using a phosphorescent polymer, which is a copolymer that has bis(2-phenylpyridine)iridium (acetylacetonate) [Ir(ppy)2(acac)], N,N′-diphenyl-N,N′-bis(3-methylphenyl)-[1,1′-biphenyl]-4,4′-diamine (TPD) and 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (PBD) as a side group. The phosphorescent polymer has an ambipolar charge-transport ability. An increase in PBD unit concentration allows an improvement in the efficiency of the PLEDs. Ba and Cs were used for electron-injection layers as well as Ca, to improve the electron injection. An external quantum efficiency of 11.8% and a power efficiency of 38.6lm∕W were obtained by using Cs. The results indicate that this can be attributed to an improvement in the charge balance of electrons and holes.

Analysis of the glass transition temperature of miscible polymer blends

Abstract: Etude theorique de la relation temperature de transition vitreuse-composition des melanges de polycaprolactone/polymere chlore