Chemical/solvent etching

The nanostructures grown by SMPs were easily detached from the substrate by ultrasonic treatment, so the material can be dispersed into organic solvents and may be used for further preparation, chemical modification (etching), assembly and other nanochemical modifications. The SMPs seem to be promising candidates for the controlled growth of nanostructures, allowing us to circumvent the complexity associated with multi-parametric situations. 

There are two general categories of etching chemical attack or bombardment with charged particles as in plasma and ion beam etching. Chemical attack can be further divided into several categories, including dissolution, which implies the removal of whole molecules of a material as it dissolves acids and other chemicals. Solvent extraction with xylene was used for the study of PE [294] however, dissolution is not recommended due to the artifacts that... 

The choice of substrate can impact the chemical and etch resistance of a coated plastic part. Thin layers of paint (especially when thin) can be influenced by the hardness of the substrate. However, this does not generally impact the chemical resistance of clear-coated parts as measured in testing such as Jacksonville. Substrates that are sensitive to solvents such as acrylonitrile butadiene styrene (ABS) and polycarbonate/polybutylene terephthalate (PC/PBT) can be rapidly or slowly degraded when attacked with certain solvents or even basic materials. 

Poly(phenylquinoxaline—arnide—imides) are thermally stable up to 430°C and are soluble in polar organic solvents (17). Transparent films of these materials exhibit electrical insulating properties. Quinoxaline—imide copolymer films prepared by polycondensation of 6,6 -meth5lene bis(2-methyl-3,l-benzoxazine-4-one) and 3,3, 4,4 -benzophenone tetracarboxyUc dianhydride and 4,4 -oxydianiline exhibit good chemical etching properties (18). The polymers are soluble, but stable only up to 200—300°C. 

Our Electronic Chemicals group is an industry leader in most basic manufacturing of Wet Process Chemistries, from UHP Straights (100 ppt qualities). Custom formulated Wet Etch, Solvents and Solvent Blends, and Cleaning Products. 

PTFE IS insoluble in all known solvents and resists attack by most chemicals, although its surtace is readily degraded by alkah metal-anunonia solutions. Such solvated electron media etch PTFE to produce a brown-black layer quite unlike the onginal white, low-friction, nonstick surface... 

A characteristic of the group (a) of resins is that they air-dry solely by solvent evaporation and remain permanently solvent soluble. This fact, combined with the need to use strong solvents, makes brush application very difficult, but sprayed coats can be applied at intervals of one hour. A full vinyl system such as (o) possesses excellent chemical and water resistance. Many members of group (o) have very poor adhesion to metal, and have therefore been exploited as strip lacquers for temporary protection. Excellent adhesion is, however, obtained by initial application of an etching primer the best known of such primers comprises polyvinyl butyral, zinc tetroxy-chromate and phosphoric acid. 

IMS can be used for chemical analysis of vapours from electronics packaging [287]. IMS-QMS has been used to analyse headspace vapours in sealed electronic packages [275,288] and to follow outgassing of polymers [287]. Various types of photoresist solvents, phtha-late plasticisers and other polymer additives, such as BHT, were detected. Other applications of IMS in semiconductor technology involve failure analysis control of the efficiency of cleaning and etching steps characterisation of process media and surveillance of the atmosphere of clean rooms. 

A number of chemical or electrochemical treatments may be applied after the forming of aluminum or aluminum alloy products. Solvent, acid and alkaline solutions, and detergents can be used to clean soils such as oil and grease from the aluminum surface. Acid and alkaline solutions can be used to etch the product or brighten its surface. Acid solutions are also used for deoxidizing and desmutting. 

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