Star-shaped amphiphilic polymeric surfactants comprising a hydrophobic polyhedral oligomeric silsesquioxane (POSS) core and hydrophilic poly(ethylene glycol) (PEG) arms with various chain lengths are successfully synthesized using copper(I)-catalysed azide-alkyne cycloaddition (CuAAC) click reaction. Their chemical structures and molecular characteristics are clearly confirmed using Fourier transform infrared and 1 H NMR spectroscopies and gel permeation chromatography, and no homopolymer is found after CuAAC click reaction. Aqueous solutions of these star-shaped polymers have been investigated using atomic force and transmission electron microscopies and dynamic light scattering studies and it is found that they can self-assemble into micelles. The sizes of the micelles can be adjusted by the length of the PEG arms, where longer chains not only lead to increased micelle sizes, but also reduce the contact angle values. Moreover, the melting points and root mean square roughness of the obtained star-shaped polymers are slightly increased on increasing the chain length of the PEG arms.
Synthesis of star‐shaped polystyrene (PS) and poly (methyl metachrylate) (PMMA) containing a polyhedral oligomeric silsesquioxane (POSS) core are fabricated by combination of atom transfer radical polymerization (ATRP) and copper (I) catalyzed azide‐alkyne cycloaddition (CuAAC) click reaction techniques. The synthetic route proceeds in two steps; firstly, clickable alkyne‐end functionalized polymeric arms and a POSS‐(N3)8 core are prepared independently by arm‐first approach using ATRP and nucleophilic substitution reaction of octa‐(3‐chloropropyl) silsesquioxane POSS‐(Cl)8 with sodium azide. Finally, the CuAAC click reactions between inorganic‐organic hybrid core POSS‐(N3)8 and alkyne functionalized PMMA and PS arms provide the targeted star‐shaped polymers. Their chemical structures and molecular characteristics are clearly confirmed by FT‐IR, 1H‐NMR, and GPC analyses. The obtained polymers are utilized as insulators for organic field effect transistors (OFETs) using perylene as an active n‐type organic semiconductor. Compared with linear PMMA and PMMA‐POSS, the POSS‐(PMMA)8 exhibited better output and transfer characteristics for the OFET device.
Three water soluble laundry polymers were employed for the first time in liquid detergent formulations for hard surface cleaning. The polymers included in the formulations were the sodium salt of maleic acid/olefin copolymer (P1, anionic), polyethyleneimine (P2, cationic), and polyethylene glycol-g-vinyl acetate (P3, nonionic). Commercially available surfactants (C 10 Guerbet alcohol alkoxylate (FAEO), caprylyl/decyl glucoside (APG), and the sodium salt of ethoxylated alkyl ether sulfate (SLES) were chosen to formulate bathroom, kitchen, and all-purpose cleaners, which provide the desired broad of pH range for hard surface applications. Their hard surface cleaning efficiencies were also compared with an amphoteric polymer (amino modified polycarboxylate, P4) as amphoteric polymers are the most suitable structures for hard surface cleaning. The standard test method and the cleaning device, the so-called cleaning robot, were used to investigate the primary cleaning performances and synergies of the chosen polymers in a hard surface cleaners system. Secondary cleaning performance tests, which indicate the effects of the hard surface cleaners on surface modification, were also performed. The results revealed that the formulations containing P3 and P4 gave the better cleaning performance for primary cleaning tests whereas only P4-containing formulations showed the significant results for secondary cleaning tests.
Pyrene end-labeled star poly(E-caprolactone)s (PCLs) with polyhedral oligomeric silsesquioxane (POSS) core were prepared by combination of copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) click chemistry and ring-opening polymerization techniques. First, E-caprolactone (E-CL) is polymerized by using 1-pyrene methanol as initiator and stannous octoate as catalyst to obtain a-pyrene-x-hydroxyl telechelic PCL with different chain lengths. Then, its hydroxyl group is converted to acetylene functionality by esterification reaction with propargyl chloroformate. Finally, the CuAAC click reaction of a-pyrene-x-acetylene telechelic PCL with POSS-(N 3 ) 8 leads to corresponding pyrene end-labeled star-shaped PCLs. The successful synthesis of pyrene end-labeled star polymers is clearly confirmed by 1 H-nuclear magnetic resonance, Fourier transform infrared, gel permeation chromatograph, differential scanning calorimeter, and thermogravimetric analysis. Furthermore, non-covalent interactions of obtained star polymers with fullerene are investigated in liquid media. Based on Raman spectroscopy and visual investigations, the star polymer having shorter chain length exhibited better and more stable dispersion with fullerene. The amount of pyrene units present per polymer chains can directly influence the dispersion stability of fullerene.
In this study, hybrid nanocomposites were synthesized by photo‐crosslinking of poly (ethylene glycol) methyl ether acrylate/poly (ethylene glycol) diacrylate monomer system using 2‐ (carboxymethoxy) thioxanthone and POSS‐(PEG2000)8. Additionally, AgNO3 was added to this formulation and in situ formation of silver nanoparticles onto hybrid nanocomposites were achieved in one‐step. UV–Vis spectroscopy technique was used as a very useful tool for surface plasmon resonance band detection of silver nanoparticles. In addition to thermogravimetric analyses which were performed in nitrogen atmosphere to determine the thermal stability of the nanocomposites, dynamic light scattering, and scanning electron microscopy techniques were also used for size and morphology of silver nanoparticles in a hybrid network. TGA analyses proved that even the addition of a very low amount of POSS‐(PEG2000)8 made noteworthy contribution to thermal stability especially in the presence of silver nanoparticles in the hybrid network. The swelling capacities of the prepared films were examined at 1, 3 and 24 h in phosphate buffer solution (pH = 7.4). It was found that film containing only POSS‐(PEG2000)8 had the highest swelling ratio in the shortest time.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.