polyimide specialty polymers are finding growing usage in applications such as high temperature, thermally stable insulators and dielectrics, coatings, adhesives, and high performance composites. to add to this already rich field of polyimide functions, we wish to review recent research from our laboratory which features the photoconductive and electrochemical behavior of polyimides, areas which have not as yet been widely explored. the first area of research, which illustrates polyimides as electrochemically active materials, is the recent work of s. mazur and s. reich. it deals with the specially controlled deposition of very thin silver layers, or certain other metal layers, into a polyimide film prepared from 4,4′-oxydianiline and pyromellitic dianhydride. this is achieved by coating the polyimide film, ∼10μm thick, onto a cathode. the cathode is placed in an electrolyte solution containing silver ion. a potential is applied between the solution and the cathode, resulting in the diffusion of silver ions towards the cathode. at steady state, when the flux of electrons (moving away from the cathode) equals that of the silver ions, a well defined, particulate, dense silver layer, ∼0.1μm thick, is deposited within the polyimide film. it is shown that the position and thickness of the metal layer as well as its geometrical shape can be controlled very precisely. the second area of research, photoconductivity in polyimides, is the work of s. c. freilich. it is found that addition of electron donors, such as dimethylaniline, to kapton® polyimide film results in an enhancement of the photocurrent generated by as much as five orders of magnitude when compared to the undoped polymer. the mechanism of the enhancement is shown to be the result of radiation absorption by a charge transfer complex formed between the added electron donor and the imide portion of the polymer backbone. excitation is followed by rapid and complete electron transfer from the donor to pyromellitimide to yield the radical anion of the polymer and the radical cation of the donor. these ion pairs are demonstrated to be the carriers of the photocurrent. they also undergo rapid back electron transfer, and the geminate recombination process is consistent with an onsager model analysis.
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polyimides are a specific polymer type which is ideal due to properties such as heat resistance and mechanical strength.
arkema offers a wide range of polyimide films, varnishes, powder and stock shapes for high-performance applications in semiconductors, evs, consumer electronics and the aerospace industry. pi material provides unmatched thermomechanical performances,
the advanced properties of polyimides are improving the manufacturing of flexible circuits, semiconductors, and other smart devices.
polyimides (pi) are a group of high performing polymers known for their exceptional chemical, thermal, and mechanical properties. polyimides are typically high strength and show excellent thermal stability across high and low temperatures. this latter attribute especially is important for fine dimensioned polyimide parts that must maintain critical tolerances. similarly, the thermal stability of polyimides
our p84®nt powder combine the outstanding properties of polyimide, such as high temperature resistance up to 350 °c, chemical resistance, high mechanical strength or minimal abrasion.
polyimide materials, as kapton®, are widely used for flexible electronics substrates or as insulators, thanks to their wide range of thermal stability as well as excellent dielectric and mechanical properties. however, there are limitations in their processability and employment in new technologies due to their low solubility and deep amber staining, resulting from charge transfer interactions established between polymer rigid chains. currently, researchers are focusing on designing resins with excellent thermal and chemical stability, transparent and colorless with a high processability in terms of viscosity and solubility. however, balancing among all those properties for this class of materials remains a big challenge today, as some of these properties seem to exclude others. in this episode, the focus will be on aliphatic anhydrides, which play a key role for the final polyimide’s properties enhancement. this will be explained by b.sc. sara greco, a chemist working on this topic (as part of her master's thesis) in the r&d department of valsynthese, a swiss cdmo specialized in hazardous chemistry.
advanced materials white polyimides thermalbright® polyimide thermalbright® polyimide is a breakthrough high temperature, highly reflective, essentially opaque, white polyimide film. typical polyimides are orange colored and highly absorptive when filled with white pigments, but thermalbright is bright white in color and contains no silicones, acrylics or non-polyimide polymers. thermalbright is highly customizable and available in […]
polyimides are usually applied in liquid form and then thermally cured as a thin film or layer to achieve the desired properties. precise temperature uniformity is essential in order to avoid cracks in the polyimide layer and color variations. for a system specifically suited to curing polyimides, visit the yes-450pb series and yes-vertacure product pages.
a polyimide is a specific type of polymer, consisting of imide monomers. polyimides are highly desirable for their strength, and insulative properties.
toray advanced composites specializes in multiple composite and carbon fiber materials and processes for the world's aerospace, space/satellite, high-performance automotive racing, high-end industrial, and athletic footwear markets.
polyimides are widely used in the mems and flexible electronics fields due to their combined physicochemical properties, including high thermal stability, mechanical strength, and chemical resistance values. in the past decade, rapid progress has been made in the microfabrication of polyimides. however, enabling technologies, such as laser-induced graphene on polyimide, photosensitive polyimide micropatterning, and 3d polyimide microstructure assembly, have not been reviewed from the perspective of polyimide microfabrication. the aims of this review are to systematically discuss polyimide microfabrication techniques, which cover film formation, material conversion, micropatterning, 3d microfabrication, and their applications. with an emphasis on polyimide-based flexible mems devices, we discuss the remaining technological challenges in polyimide fabrication and possible technological innovations in this field.
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polyamides and polyimides are often confused due to their similar names, but they are very different in chemical and mechanical properties.
polyimides (pis) represent a benchmark for high-performance polymers on the basis of a remarkable collection of valuable traits and accessible production pathways and therefore have incited serious attention from the ever-demanding medical field. ...
polyimides suppliers
as high-performance polymers become more mainstream, it becomes tougher to choose which solutions to apply to a given application. peek and polyimide are among the two toughest polymers out there. but how do they compare with one another?
we examine the myths surrounding polyimide tubing and discuss its advantages for medical applications, especially minimally invasive surgical devices.
master bond offers a full line of epoxy adhesives for the bonding of polyimide substrates.
advanced materials clear / colorless polyimides nexolve’s core polymer technology is clear and colorless polyimides. nexolve specializes in three varieties of colorless polyimides that can be tailored to meet demanding applications in display applications, space structures, thermal insulation, electrical insulators, industrial tapes, and advanced composites. cp1 polyimide cp1 provides superior physical and electrical properties over […]
2021 volume 4 issue 3
discover the ultimate champion of polymers! our polyimide film and materials offer exceptional heat resistance and strength. shop the top polyimide solution today! read more.