Papers by Keyword: NMP

Abstract: Polyether sulfone (PES) stands as a widely utilized polymeric membrane in separation technology. However, due to certain undesirable drawbacks encountered in its application, researchers consistently strive to enhance its characteristics and performance. In this study, we delve into the effects of Mg(OH)₂ addition on the characteristics and performance of PES membranes employed for humic acid removal from water. The membrane fabrication involves PES as the primary polymer, NMP as the solvent, and a blend of ethanol and water as non-solvents. Characterization of the membranes encompasses the assessment of functional groups via FTIR, morphological structure through SEM imaging, and porosity evaluation. Notably, the Mg(OH)₂ additive exerted a positive influence on the prepared PES membranes, leading to discernible alterations in the morphological structure, as evident in SEM cross-sectional images. The augmentation of Mg(OH)₂ concentration resulted in increased membrane porosity. The FTIR spectra revealed the presence of water derived from Mg(OH)₂ crystals. The research yielded notable results, with the most outstanding membrane exhibiting a pure water flux of 41.6 L/m2·h and a rejection rate of 71%. Furthermore, it displayed a Water Flux Recovery Ratio (FRR) of 72%. These findings underscore the effectiveness of incorporating Mg(OH)₂ as an additive in enhancing the performance of PES membranes for humic acid removal, with promising implications for water purification applications.

Abstract: Tetramethylammonium hydroxide (TMAH) and N-methyl pyrrolidinone (NMP) are commonly used in photoresist developing and stripping process, however, both of TMAH and NMP have been confirmed with CMR (Carcinogenic, Mutagenic and Reprotoxic) concerns. With more attention attracted to TMAH and NMP replacements, Huntsman developed a range of new quaternary amines products, including E-GRADE^® Choline OH (Choline Hydroxide), E-GRADE^® THEMAH (Tris (2-hydroxyethyl) methylammonium Hydroxide), XHE-125, XHE-128, XHE-138, XHE-145 and XHE-148, and solvents, E-GRADE^® MEOX (3-Methyl-2-oxazolidinone) and XHE-123, which have been evaluated in comparison with the performance of TMAH and NMP.

Abstract: Efficient visible light active TiO₂-Molybdenum sulphide (TiO₂-MoS₂) composites were prepared by solvothermal methodfrom titanium isopropoxide and commercial MoS₂ using N-methyl 2-pyrrolidone (NMP) and isopropanol (IPA) solvent mixture. Extended absorption band edge and enhanced visible light absorbance are supplemented intothe TiO₂-MoS₂ composites by this method. While TiO₂ shows ~48% visible light photodegradation of rhodamine B (RhB) the TiO₂-MoS₂(0.24) exhibits~74% of degradation. In addition to the visible light enhancement, very high surface area and reduced charge transfer resistance at the interfaces are attributed to the enhanced activity of the composite.

Abstract: Poly (lactic acid) (PLA) has many potential uses, for example as packaging, textiles, biomedical fields, including suture, bone fixation material, drug delivery microsphere, and tissue engineering. However, PLA shows the poor toughness, slow degradation rate and relatively hydrophobic. The aim of this study was to investigate the ability of N-methyl-2-pyrrolidone (NMP) to improve the characteristics of PLA film. PLA films were prepared using a solvent casting method and their various properties were investigated. From tensile strength (TS), elongation at break (E) and young’s modulus (ε) determinations, the incorporated PLA films exhibited the softer behavior than plain PLA film. On the other hand, from the contact angle and surface free energy values, the PLA films incorporated with NMP could improve the wettability of solvents and also increased % water sorption (WS) and % weight loss (WL) than PLA films with NMP dose dependent. However SEM photographs revealed the more rather rough and cracked surface as the higher amount of NMP was incorporated in PLA film.

Abstract: The introduction of metal gates and high-k dielectrics in FEOL and porous ULK dielectrics in BEOL presents severe issues [1] and leads to the requirement of new chemistries and processes. A major challenge in cleaning is the removal of photoresist (PR) in both FEOL and BEOL. In current semiconductor device fabrication flow, the photoresist strip process in FEOL is mostly achieved by applying a sequence of plasma ashing followed by a wet-clean step with sulfuric-peroxide mixture (SPM). But in general, ashing leads to strong oxidation or etching of silicon substrate. Hence, several approaches for ashless PR strip have been reported, such as hot SPM [2] and the combination of a pre-treatment using high velocity CO2 aerosol [3].

Abstract: High velocity aerosol cleaning using ultrapure water or dilute aqueous solutions (e.g. dilute ammonia) is common in semiconductor IC fabrication [1]. This process combines droplet impact forces with continuous liquid flow for improved cleaning efficiency of sub-100nm particles. As with any physically enhanced cleaning process, improved particle removal can be accompanied by increased substrate damage, especially to smaller (<80nm) features [2]. Solvents such as N-methylpyrrolidone (NMP) and tetrahydrofurfuryl alcohol (THFA) are used for resist strip applications [3]. It is possible, and sometimes useful, to deliver these solvents through the same spray nozzle normally used for aqueous spray cleaning. In this presentation we explore the particle removal and substrate damage performance of 2-ethoxyethanol (EGEE), NMP and THFA as used in a conventional aerosol spray cleaning system