Water-soluble Polysiloxane Research Articles

Water-soluble polysiloxane sizing for improved heat resistance of basalt fiber

Basalt fiber is widely applied in composite materials. Recent years, it has a new application in filter bags. But commercial sizing agent always decomposes at 300 °C, which limits the application of basalt fiber above 300 °C. To solve this problem, in this study, a water-soluble polysiloxane sizing agent was synthesized and used to coat basalt fiber to improve its heat resistance. TG-DSC results showed the polysiloxanes starts to decompose at 370 °C. SEM and AFM results indicated that the surface of the fiber was wrapped by an organic coating. Abrasion tests showed friction factors of basalt fibers were decreased by the coating. XPS study showed there was a chemical connection between the layer and surface. Results of contact angles showed the surface energies of the fiber have increased after coated. Mechanical tests showed the breaking force of the coated basalt fiber could be maintained above 76% at 300 °C, which was 3.8 times that of unsized fiber, and kept above 49% at 400 °C, which was 2.4 times that of unsized fiber.

Water-soluble polysiloxane for drug delivery in bioimaging

Polysiloxane based on N-2-hydroxy-1,1-di(hydroxymethyl)ethyl-N’-3-triethoxysilylpropylurea was synthesized. The polymer forms small nanoparticles and their associates in water. The latter can retain poorly soluble luminophore and hydrophobic gadolinium complex. The doped particles are capable of interacting with proteins. Aqueous suspensions based on non-toxic siloxane nanoparticles can be used for visualization of results of assays of biological objects (bioimaging) by fluorescence and magnetic resonance tomography.

Interpenetrating polymers networks derived from silylated soybean oil and water soluble polysiloxanes

ABSTRACTA series of interpenetrating polymer networks (IPNs) with different compositions were prepared from emulsions of silylated soybean oil (SilSoy) and hydrophilic polysiloxanes (HPPS). Silylation of the soybean oil was achieved via the “Ene reaction” and the water soluble polysiloxanes were prepared by hydrolysis and condensation polymerization of 3‐aminopropyldiethoxymethylsilane followed by a reaction with ethylene carbonate. Unlike the triglyceride structure of SilSoy, HPPS are water soluble, linear polysiloxanes having a pendant hydroxyl group on every siloxane. Evaporation of the water phase from emulsions of SilSoy in aqueous solutions of HPPS yielded crosslinked IPN films composed of silanols and carbinol condensations that formed stable siloxanes (SiOSi) crosslink linkages as well as hydrolysable silicone‐carbinol (SiOC) linkages. The entangled network that was obtained is characterized by intimate mixing of these incompatible phases with a typical IPN microphase separation. The crosslink density between the dispersed phase and the continuous phase was correlated with the swell‐gel data. The mechanical and thermal properties were also studied and were correlated with the composition and the crosslinks density. These IPNs can be used as convenient environmentally degradable control release systems via the hydrolysis of the SiOC linkages. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47182.

Regulating photochemical behavior and property of imidazolium-based water soluble polysiloxane macromolecular photoinitiators by anions

Five polysiloxane macromolecular photoinitiators containing different anion structures with ionic liquid character ([Si-di2959Im][X] (X = Br−, Ph4B−, TsO−, NO3−, CF3COO−)) were designed and synthesized. The effect of different anion structures on photochemical behavior, phoinitiating mechanism, the water solubility, thermal property and volatility of the photoinitiators was systematically explored. [Si-di2959Im][X] have high extinction coefficient that reaches up to 40,210 M−1 cm−1, and similar photoinitiating activity and mechanism to 2-hydroxy-1-[4-(2-hydroxyethoxy) phenyl]-2-methylpropan-1-one (Irgacure 2959), while the photopolymerization induction periods of the TPGDA systems initiated by [Si-di2959Im][X] (X = Ph4B−, CF3COO- and NO3) are slightly shorter than that by Irgacure 2959. In addition, [Si-di2959Im][X] have not only good water solubility, but also desirable thermal property and low saturated vapor pressure. The order of water-solubility of [Si-di2959Im][X] is Ph4B− <Br− <TsO− <NO3− <CF3COO−, the order of the saturated vapor pressure is CF3COO− < Ph4B−< NO3−< Br− < TsO−. High-performance liquid chromatography chromatograms reveal that the migration of the photolysis fragments of [Si-di2959Im][X] from the cured material is mitigated significantly by their high molecular weights.

Polyfunctional Siloxane Water-Soluble Nanoparticles for Biomedical Applications

Hydrolysis of N-methyl-N-(2,3,4,5,6-pentahydroxyhexyl)-N′-(3-triethoxysilylpropyl)urea gave water-soluble polysiloxane nanoparticles. They can be used for the preparation of intensely luminescent stable aqueous suspensions of water-insoluble or poorly soluble compounds (Eu(BTFA)3 · 6H2O complex and tetracyano-tetraaryl-porphyrazines) for biomedical applications, in particular, for bioimaging.

An unconventional chromophore in water-soluble polysiloxanes synthesized via thiol-ene reaction for metal ion detection

The unconventional chromophore S → Si coordination bonds is firstly found in water-soluble comb polysiloxanes (PETHs) with different ratios of polyether and mercaptopropyl groups as side chains. The PETHs are synthesized via efficient thiol-ene click reaction between polymercaptopropylmethylsiloxane (PMMS) and 2,5,8,11,14,17,20,23-octaoxahexacos-25-ene. The fluorescence is preliminarily assumed to be generated from through-space charge transfer because the S → Si coordination bonds make it easier to occur. The existence of S → Si coordination bonds is firstly proved by experiments, including synthesizing model compound and testing via quantum-chemical modeling (Digambara Patra, 2001), Si NMR, XPS spectra, and fluorescence spectra. Furthermore, the changing law of fluorescence intensity of those compounds with temperature, concentration and solvent are investigated. Fluorescence intensity improves with the temperature dropped down. This unconventional chromophore shows the AIEE (Valeur and Berberan-Santo, 2017) (aggregation-induced emission enhancement) phenomenon. The mercapto and thioether groups in PETHs can act on Hg2+ and Fe3+, breaking the SiS interaction and quenching the fluorescence. The quenching constant is determined by the Stern–Volmer equation. Therefore, the PETHs are used as fluorescence probes for Hg2+ and Fe3+ in water which may be applicable to metal detection.

Water Soluble Polysiloxanes

Water soluble polysiloxanes were prepared by condensation of 3-aminopropyl diethoxymethylsilane followed by the reaction of the amines with ethylene carbonate to yield carbamate side chains with terminal hydroxyl groups attached to each silicon atom in the polymer chain. The molecular weight of these carbinol functional polysiloxanes was controlled by adding known concentrations of hexamethyldisiloxane during the polycondensation reaction. The structure of these polymers was confirmed by 1H NMR and FTIR. The resulting polysiloxanes are water soluble and their solubility is independent of the pH or the molecular weight of the polymer. Furthermore, no additives are needed in the water to enhance the solubility of these polymers. The mechanical properties of films that were cast from water solutions were studied and indicated the presence of strong hydrogen bonds that provide for elastomeric films with no need for additional crosslink agents. The hydrophilic nature of the polymer was further confirmed by contact angle measurements and thermal properties data clearly indicate the presence of bound water associated with the large number of hydroxyl groups in the polymer. SEM images of paper coatings prepared from these polysiloxanes revealed a smooth surface with no apparent structural defects that can be used as an anti-graffiti coating.

A novel water-soluble polysiloxane for biomedical applications

ISSN 00125016, Doklady Physical Chemis try, 2013, Vol. 453, Part 2, pp. 282–287. © Pleiades Publishing, Ltd., 2013.Original Russian Text © E.Yu. Ladilina, T.S. Lyubova, Yu.P. Klapshin, M.A. Lopatin, V.V. Semenov, G.A. Domrachev, 2013, published in Doklady Akademii Nauk, 2013, Vol. 453,No. 6, pp. 634–640.

Self-floating ability and initiating gradient photopolymerization of acrylamide aqueous solution of a water-soluble polysiloxane benzophenone photoinitiator

Three water-soluble polysiloxane benzophenone photoinitiators (W-Si-HBP2-A/B/C) with various silicon content used for preparing a gradient polymer were synthesized based on the traditional photoinitiator 4-hydroxybenzophenone (HBP) and aminopolysiloxane. The structures were confirmed by proton nuclear magnetic resonance (1H NMR), and gel permeation chromatography (GPC). The water solubility of the photoinitiators, the effect of the silicon content on their triplet state lifetimes and photopolymerization property and the self-floating ability in the water system, and the internal connection between the surface morphology and property of the gradient polymer and film initiated by the photoinitiators were investigated. All three photoinitiators showed relatively good solubility in water, and longer triplet lifetimes and a smaller rate constant than HBP. It is found that the photoinitiator with the highest silicon content had the best floating capability due to lower surface tension and energy of polysiloxane. By using this photoinitiator, the gradient polymer with a significant molecular weight gradient was obtained. In addition, the polysiloxane-based photoinitiators can decrease the dispersion surface energy of the gradient polymer, and the increase of photoinitiator content can change the microstructure of the gradient polymer film. The new green method for preparing gradient polymeric material by using the polymerization technology and the water-soluble polysiloxane-based photoinitiators may have potential applications in the green chemical industry.

Synthesis, film morphology, and performance of functional polysiloxane bearing polyether and benzophenone derivative side groups

A water-soluble polysiloxane (PE-PUVSi) bearing functional benzophenone derivative and hydrophilic polyether side groups was successfully synthesized by hydrosilylation of polyhydromethylsiloxane (PHMS) with 2-hydroxy-4-(β-allyloxy-γ-hydroxy)propyloxy benzophenone (MUV-O) and allyl polyoxyethylenepolyoxypropylene ether (F6). The chemical structure, film morphology, and performance of the synthesized polysiloxane were investigated and characterized by spectral analysis, atomic force microscope (AFM), Kawabata evaluation system (KES), and other instruments. Experiment results indicate that PE-PUVSi had an intensive UV-absorbing capacity at wavelengths of 243.6, 289.2, and 325.0 nm. It formed a hydrophilic polysiloxane film on both the fiber and the silicon wafer surface. On the wafer surface, PE-PUVSi actually showed non-homogeneous and phase-separated microscopic film morphology. In addition, PE-PUVSi could provide a bulky softness, good wettability, and antistatic property for the treated fabric and make the treated cotton fabric show a low UV transmittance at the wavelengths between 270 and 330 nm.

Function and performance of silicone copolymer (VI). Synthesis and novel solution behavior of water-soluble polysiloxanes with different hydrophiles

Silicone surfactants containing different pendant hydrophilic groups such as diethanol tertiary amine (SHE, nonionic), diethanol methyl quaternary amine (cationic) and triethyl quaternary amine (cationic) have been synthesized and characterized by 1H and 13C NMR and gel permeation chromatography. The solution behavior of these novel surfactants has also been investigated by surface tension measurement and a fluorescence method. It has been observed that the surface tension of these surfactants decreases as a function of time at a very low polymer concentration (1 × 10−4 wt%). At higher concentration (0.1 wt%), the equilibrium surface tensions reached very low values compared to that of typical polymer surfactants, for example, poly(ethylene oxide–propylene oxide) block copolymer (EPE0.8). In addition, the low I 1/I 3 values of these silicone surfactants indicate the formation of polymer aggregates in aqueous solution, and an extremely low I 1/I 3 value of SHE (1.06) compared to other polymeric surfactants (EPE0.8) and conventional surfactants [poly(ethylene glycol n-nonyl phenyl ethers), cetyltrimethylammonium bromide, and sodium dodecyl sulfate] indicates its stronger hydrophobicity.

Water-soluble polysiloxanes with pendant 1-oxypyridin-3-yl groups

Polysiloxanes with 1-oxypyridin-3-yl groups bonded to silicon were prepared by base-catalyzed hydrolysis-polycondensation of dialkoxy silane monomers. The polymers were characterized by IR,1H-NMR, and13C NMR spectra. Polymers bearing 1-oxypyridin-3-yl functions were soluble in organic solvents like CH2Cl2 or MeOH. The solubility in H2O increased with increase in molecular weight. The distribution coefficient for materials with different molecular weight in a water/CHCl3 mixture is reported. Quasi-elastic light-scattering data indicate that the Stokes diameter for the polymer with molecular weight 9000 increases in the order H2O<MeOH<CH2Cl2. Structural ramifications of the solvent effect are suggested.