Control of Reflectivity and Surface Conductivity in Metallized Polyimide Films Prepared via in Situ Silver(I) Reduction

Abstract

Optically reflective and surface-conductive polyimide films have been prepared by the incorporation of silver(I) acetate and trifluoroacetylacetone into a dimethylacetamide solution of the poly(amic acid) formed from 3,3′,4,4′-benzophenonetetracarboxylic acid dianhydride (BTDA) and 4,4′-oxydianiline (4,4′-ODA). Thermal curing of the silver(I)-containing poly-(amic acid) leads to imidization with concomitant silver(I) reduction, yielding a reflective and conductive silver surface if the silver(0) concentration is greater than ca. 12% by weight and the film is cured to a final temperature of 340°C. The metallized BTDA/4,4′-ODA films retain the essential mechanical properties of undoped films and have good thermal stability particularly in nitrogen atmospheres. The bulk of the polymer is not electrically conducting. Films were characterized by X-ray, DSC, TGA, XPS, TEM, SEM, and AFM.

Inverse CVD: A Novel Synthetic Approach to Metallized Polymeric Films

“…Reflectivity, Conductivity, and Surface Characterization Results Table 1 displays data for four silvered BTDA/4,4¢-ODA polyimide prepared with AgTFA, [2,8] AgHFA, [9,10] (trifluoroacetato)silver(I), AgTFAA, [11] and h 4 -1,5-cyclooctadiene (hexafluoroacetylacetonato)silver(I), [12] AgHFA(COD).…”

Preparation of silvered polyimide films with reflective and electrically conductive surfaces using single‐stage self‐metallization techniques and factors affecting silver particles migration

“…Talor and coworkers 6 suggested that free-rotational structures, such as carbonyl groups in dianhydride and diamine, help to form both highly reflective and conductive silvered PI films using supercritical fluid infusion of silver methods. 7 Among many kinds of silver(I) complexes, the in situ formed AgTFA from silver(I) acetate and 1,1,1-trifluoro-2,4-pentanedione (HFAH) in DMAc is the favorite one because the precursor acetate salt is readily available with high purity, is thermally and photochemically stable, and the acetate anion has moderate Bronsted basicity. 3 In our study we chose the in situ AgTFA complex, the carbonyl-containing 3,3 0 ,4,4 0 -benzophenone tetracarboxylic acid dianhydride (BTDA), and the carbonyl-containing 4,4 0 -diaminobenzophenone (DABP) in an effort to produce both reflective and conductive silvered PI films by using the ICVD method.…”

New Metalized Polyimide Films Structure and Physical Properties

“…From this it follows that along with the factor of crystallite sizes in the silver coating, the morphology, or degree of "polishing", also plays a major part. In some works [5][6][7] the silver layer formation is carried out by high temperature thermolysis of silver in the films. Here during thermolysis the dehydrocyclisation takes place with water evolving and formation of a loose surface.…”

“…At present the main metallization methods include homogenous addition of metal compounds (salts or coordinating complexes) into the prepolymer solution with subsequent film casting [4][5][6][7] or the superfluid [8] impregnation of metal compounds into polyimide films. The modified films are then treated at high temperature (5-7 hours at no lower than 300 °C).…”