While the performance of polymer−polymer bulk heterojunction organic photovoltaics (OPVs) is poor compared with polymer−fullerene OPVs, reducing or eliminating micrometer-scale phase separation in all-polymer OPVs may dramatically improve performance. Herein, we demonstrate that 2-ureido-4[1H]-pyrimidinone (UPy) quadruple hydrogen bonding interactions can be used to prevent micrometer-scale pha...

In this review, progress towards a fundamental understanding of the rheologymorphology relationship in immiscible polymer blends is discussed. The behaviour of biphasic polymer fluids, containing Newtonian components and subjected to simple shear flows is relatively well understood at present. The behaviour of these “simple” blends will be discussed first, as it serves as a reference for the ot...

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We demonstrate that macromolecules in miscible polymer blends may behave as good, Theta, and poor polymeric solvents for each other. We construct a conceptual phase diagram, delineating the range of validity of the random-phase approximation, outside of which polymers contract or expand beyond their unperturbed dimensions, contrary to common assumptions. Remarkably, the correlation length for p...

We reviewed recent advances in high-performance organic field-effect transistors (OFETs) based on organic semiconductor/insulator polymer blends. Fundamental aspects of phase separation in binary blends are discussed with special attention to phase-separated microstructures. Strategies for constructing semiconductor, semiconductor/dielectric, or semiconductor/passivation layers in OFETs by blen...

Fullerenes have been shown to intercalate between the side chains of many crystalline and semicrystalline polymers and to affect the properties of polymer:fullerene bulk heterojunction solar cells. Here we present the first in-depth study of intercalation in an amorphous polymer. We study blends of the widely studied amorphous polymer poly(2-methoxy-5-(30,70-dimethyloctyloxy)-p-phenylene vinyle...

Solution-processed polymer optoelectronic devices such as light-emitting diodes and solar cells have many advantages for large-area manufacture, and show increasing levels of performance. Here, we review recent progress in using blends of two conjugated polymers for optoelectronic devices. The blending of two or more polymers allows tuning of device performance, and for photovoltaics presents a...

The effect of gamma irradiation on micro-hardness of polymer blends of poly (ethyl methacrylate)(PEMA) and poly (ethylene oxide) (PEO) has been investigated to detect the radiation induced crosslinking. The blend system comprises a noncrystallizable polymer, PEMA and a crystallizable polymer, PEO. On irradiation, the overall hardness of the blend specimens for different dose levels infers occur...