Waterborne Poly Research Articles

Preparation and properties of waterborne epoxy resin modified by poly(meth)acrylates containing long fluorinated side chains

Two waterborne poly(meth)acrylates containing fluorinated side chains (PALF and PASF) were synthesized by conventional radical copolymerization. Then waterborne epoxy composites with hydrophobic surface were obtained through a phase-inversion emulsion technique, using the PALF and PASF acrylates as reactive surface additives. Contact angle measurements and X-ray photoelectron spectroscope were employed to characterize the surface properties and the results confirmed that the fluorine atoms in the longer fluorinated side chains migrated to the outmost layer more efficiently. The effect of the fluorinated content and the length of the fluorine side chain on thermal and bulk properties of the waterborne epoxy resin was investigated. With increasing the fluorinated content or the length of the fluorine side chain, the contact angles and thermal properties improved while the mechanical properties showed no deterioration.

Triblock copolymers containing hydrophilic PEO blocks as effective polyols for organic solvent-free waterborne poly(urethane-urea)s

The structure, morphology and final properties of synthesized waterborne poly(urethane-urea)s (WPUU) based on triblock copolymers containing hydrophilic poly(ethylene oxide) PEO block as polyol has been studied. Different molecular weight poly(ethylene oxide-b-propylene oxide-b-ethylene oxide) (PEO-b-PPO-b-PEO) and poly(propylene oxide-b-ethylene oxide-b-propylene oxide) (PPO-b-PEO-b-PPO) triblock copolymers were used as polyols acting as soft segment. A Volatile Organic Compounds (VOCs) free synthesis procedure was followed to synthesize WPUU dispersions. Particle size, solid content and viscosity of the WPUU dispersions were measured. Atomic force microscopy was used to study the morphology, whereas size exclusion chromatography helped determining molecular weight of the WPUU films, prepared by solvent casting. Chemical structure was determined by FTIR and 1H NMR. Moreover, transmittance and thermal and mechanical properties of the WPUU films were also investigated. The use of PEO-b-PPO-b-PEO triblock copolymer led to dispersions with higher molecular weights and viscosities. WPUU films based on this triblock copolymer showed better mechanical properties, nevertheless they exhibited a lower transparency. All triblock copolymer based WPUU films led to nanostructured materials, which can act as template for dispersion of different kind of fillers extending possible application of waterborne polyurethanes. This work spotlights the possibility to synthesize waterborne poly(urethane-urea) dispersions with tailored properties using triblock copolymers as polyols.

Phase inversion, formation and stability mechanism of poly(urethane-acrylate) nanoemulsions based on block-copolymer surfmer

We reported herein the synthesis of block copolymers and their application in the in-situ emulsion polymerization of waterborne poly (urethane-acrylate) (WPUA) nanoemulsions based on phase inversion process. The polymerizable surfmers containing terminal unsaturated double bonds (MSA-r) were successfully synthesized via catalytic chain transfer polymerization (CCTP). Random copolymer (MSA-t) prepared through radical polymerization was utilized as control. The structure, surface tension and aggregation behavior of surfmers were characterized. The phase inversion, formation and stability of WPUA nanoemulsions were systematically investigated. Effects of MSA-r surfmer content and BMA/MMA ratio on the water resistance and thermal stability of the corresponding films were also discussed. It was found that the phase inversion mechanism of PUA prepolymer in the presence of MSA-r surfmers is different from conventional polyurethane prepolymer. The addition of MSA-r and MSA-t surfmers alters the rheological behaviors of PUA prepolymer via PUA-surfmer interactions, as well as the phase inversion process. Compared with WPUA/MSA-t emulsion, WPUA/MSA-r nanoemulsion displayed improved stability at higher solid content. The minimum particle size of WPUA/MSA-r nanoemulsion was 88.7 nm and kept almost constant after 12-month storage, while the particle size of WPUA/MSA-t emulsion was 131.3 nm and increased to 178.9 nm. Moreover, the WPUA/MSA-r film possessed improved water resistance and thermal stability.

Fabrication of NCC-SiO2 hybrid colloids and its application on waterborne poly(acrylic acid) coatings

Nanocrystalline cellulose and nano SiO2 (NCC-SiO2) hybrid colloid was synthesized by in situ polymerization using a template of NCC. The prepared NCC-SiO2 hybrid colloid was then introduced to waterborne poly acrylic acid (PAA) coatings. NCC template could inhibit an aggregation of nano SiO2, leading to a uniform distribution of SiO2 in PAA coatings. Furthermore, a formation of crosslink network of hydrogen bonding improved interfacial compatibility in a system of NCC, SiO2 and PAA. Compared to the individual NCC and nano SiO2, NCC-SiO2 hybrid colloid had an obvious improvement on the mechanical performance and the transmittance of waterborne PAA coatings. With 5 wt% NCC-SiO2 hybrid colloid, PAA coating had maximum mechanical properties, with corresponding to 6H in hardness, and level-0 in adhesion, respectively. Moreover, PAA coatings with 5 wt% NCC-SiO2 hybrid colloid had a higher transmittance of 41.8% at 390 nm.

In-situ polymerization and characteristic properties of the waterborne poly(siloxanes-urethane)s nanocomposites containing graphene

In this study, graphene oxide (GO) was chemically reduced into reduced GO (RGO) by using hydrazine and a series of waterborne RGO/poly(siloxane-urethane) (SWPU) nanocomposites with various amounts of RGO were synthesized through in-situ polymerization. Siloxane units were incorporated into the nanocomposites to cause the cross-linking reaction in polyurethane (PU) units. Changes in the structure of the nanocomposites were examined through X-ray diffractometry (XRD). The results revealed two broad peaks at 2θ = 10° and 20°, indicating the existence of short-range ordering in the hard domains. The relative intensities of the two XRD peaks varied with the RGO content orderly. Additionally, thermogravimetric analysis, dynamic mechanical analysis, tensile testing, hardness measurement, and thermal conductivity analysis were conducted to investigate the thermal and mechanical properties of the nanocomposites. The results suggest that the thermal decomposition temperature (Td), dynamic glass transition temperature (Tgd), tensile strength, and Young’s modulus were at their optimal levels with 0.3 wt% of RGO, and an RGO amount greater than 0.3 wt% weakened the thermal and mechanical properties of the nanocomposites. The surface morphology of the nanocomposites was determined using a scanning electron microscope, atomic-force microscope and contact angle meter. The results suggest that surface roughness and contact angle increased considerably with RGO content. In addition, the electrical and thermal conductivities of the nanocomposites increased with increasing RGO content.

Synthesis and characterization of environmentally-friendly waterborne poly(urethane-urea)s

In this work, corn-based 100% renewable carbon poly(trimethylene ether glycol) (P3MG), biodegradable and biocompatible poly(ethylene oxide) (PEO), 4,4′-diphenylmethane diisocyanate (MDI) and sodium 2,4-diamino-benzenesulfonate (SDBS) were used to synthesize novel biobased waterborne poly(urethane-urea) (WPUU) dispersions following an environmentally-friendly process, which avoids the use of organic solvent. The particle size of WPUU dispersions were determined by dynamic light scattering. The molar ratio of PEO/P3MG polyols was varied to identify the WPUU dispersion with the optimum equilibrium between renewable content and final properties. Increase of P3MG content in polyol mixture led to smaller particle size, what could be related to the hydrophilic character of PEO. All investigated WPUU films were characterized by means of their physicochemical, thermal and mechanical properties, as well as their morphology by atomic force microscopy. Higher P3MG content in the WPUU films led to phase separation at the nanoscale, higher glass transition temperature and T1 endotherm temperature induced by the decrease in the hydrogen bonding between soft segment and hard segment. Moreover, higher P3MG content also resulted in higher modulus and elongation at break of the WPUU films. The present work highlights that waterborne poly(urethane-urea) dispersions with promising properties can be successfully prepared without using any catalyst and organic solvent.

Preparation and characterization of UV curable waterborne poly(urethane-acrylate)/antimony doped tin oxide thermal insulation coatings by sol-gel process

Abstract The composite of waterborne poly(urethane-acrylate) (WPUA) and antimony doped tin (ATO) was a promising thermal insulation coatings for energy-saving glass. This work demonstrated a sol-gel approach for fabricating WPUA/ATO composites with improved dispersion of ATO nanoparticles. This approach was mainly concerned with the polymerization of C C bonds pre-attached to WPU and ATO nanoparticles. Surface modification was key for achieving a good dispersion of ATO nanoparticles. With UV-assisted initiation, the conversion of C C bonds reached ∼93% in 40 s. The comparison study demonstrated that resulting ATO-filled WPUA coatings outperformed those made by physical blending method over the mechanical and optical properties owing to a good dispersion of ATO nanoparticles. In particular, the coatings filled with 3 wt% ATO reduced the temperature of a designed “room” by ∼10 °C than un-filled counterparts, but merely blocked ∼16% visible light.

Thiol-ene miniemulsion polymerization of a biobased monomer for biomedical applications

Herein, we present the synthesis and characterization of poly(thioether-ester) nanoparticles via thiol-ene miniemulsion polymerization using a biobased α,ω-diene diester monomer, namely dianhydro-d-glucityl diundec-10-enoate (DGU), synthesized from 10-undecenoic acid (derived from castor oil) and isosorbide (derived from starch). DGU was copolymerized with 1,4-butanedithiol by thiol-ene miniemulsion polymerization resulting in waterborne poly(thioether-ester) particles with diameter around 200nm. Polymers with number average molecular weight up to 11kDa were obtained via miniemulsion polymerization. DSC and XRD analyses indicated a semi-crystalline polymer with a degree of crystallinity of at least 20% and Tm around 68°C. In addition, Coumarin 6 was encapsulated in the polymer particles with efficiency up to 98%. Nanoparticles presented biocompatibility in murine fibroblast (L929) and uterine colon cancer (HeLa) cells. The substantial cellular uptake of poly(thioether-ester) nanoparticles by HeLa cells suggests a potential use in uterine colon cancer treatment.

Effect of ionic monomer concentration on latex and film properties for surfactant-free high solids content polymer dispersions

Sodium styrene sulfonate (NaSS) was used to stabilize waterborne poly(methyl methacrylate/butyl acrylate) dispersions obtained by surfactant-free seeded semicontinuous emulsion polymerization at 50wt% solids content. The effect of NaSS concentration (0.175–3.6wbm%) on the reaction kinetics, NaSS incorporation onto particles, colloidal stability and properties of emulsifier-free latexes and films was investigated.It was found that fraction of NaSS that was incorporated onto polymer particles increased with its concentration due to the increase of the ionic strength, which shifted the adsorption equilibrium of the NaSS containing oligoradicals towards the polymer particles. Properties of the latexes (freeze-thaw and salt stability) improved with the concentration of NaSS and its incorporation. The lack of migration and formation of aggregates of the stabilizing moieties in the polymer films was demonstrated by water contact angle measurements and AFM images. This resulted in improved properties of the films (gloss, water uptake and mechanical strength).

Real-Time Monitoring of the Dispersion Stability of Poly(Carbonate Urethane)s Using the Turbiscan Technique

Waterborne poly(carbonate urethane) dispersions (WPCUDs) have received much attention from both academia and the chemical industry due to their potential applications in high-performance volatile organic compound-free coatings and adhesives. Commercially, both the long-term stability and the mechanical properties of WPCUDs are extremely important because these are closely related to the storage life of the product. This study provides a detailed, real-time investigation into the dispersion stability of WPCUDs. Various WPCUDs with different ionic contents and containing polyols of different molecular weights were prepared, and their dispersion stabilities were monitored in real-time using Turbiscan measurements. The effect of temperature and concentration on dispersion stability was also examined. The thermal and mechanical properties of WPCUD were characterized by thermogravimetric analysis, differential scanning calorimetry, and universal testing machine, and the data were correlated to the dispersion stability data.

스피커 댐퍼용 아미노실란 처리 수분산 폴리우레탄/에폭시 하이브리드 수지의 합성

스피커 댐퍼용 아미노실란 처리 수분산 폴리우레탄/에폭시 하이브리드 수지의 합성

Synthesis, characterization and investigation of methyl orange dye removal from aqueous solutions using waterborne poly vinyl pyrrolidone (PVP) stabilized poly aniline (PANI) core–shell nanoparticles

Waterborne polyaniline (PANI) core–shell nanoparticles were synthesizedviachemical oxidation of aniline in aqueous acidic medium using polyvinyl pyrrolidone (PVP) as stabilizer.

Fabrication and evaluation of one-component core/shell structured latex adhesives containing poly(styrene) cores and poly(acrylate) shells

A one-component, non-crosslinked, and ambient temperature-cured core/shell (CS) structured waterborne poly(styrene-acrylate) (PStA) latex adhesive was prepared by two-stage seeded emulsion polymerization. The first-stage polymers were non-polar styrene-based copolymers with Tgs ranging from 86°C to 41°C and the second-stage polymer was polar acrylate-based copolymer having a Tg of 8°C. The effect of latex particle morphology and film microstructure on the CS structured PStA latex adhesive was examined by evaluating film thermal properties and mechanical performance. The results have shown that incorporation of soft shell polymers into hard core polymers can improve adhesive properties without compromising film-forming ability. Wood adhesive performances of latex adhesive were measured by shear strength and boiling water resistance of glued wood blocks. The utilization performances of the one-component CS structured PStA latex adhesive were found to largely depend on CS morphological character and the interfacial compatibility between various polymeric constituents, demonstrating that fabrication of CS latex particles provides a promising approach to realize high-performance latex adhesives.

Novel high solid content Nano Siliconated poly (VeoVa-acrylate) Terpolymer latex for high performance latex paints

In view of good water repellency, weather resistance, and thermal stability of emulsion lattices, the present work aimed to prepare modified polyacrylate-based lattices containing silicone polymer, therefore, a conventional seeded emulsion polymerization was prepared by K2S2O8-initiation and by core/shell technique of three monomers namely MMA, BuA, and VeoVa-10, and a silicone monomer, namely, vinyltrimethoxy silane (VTMS). As a result, stable modified polyacrylate-based lattices with improved physico-mechanical properties were obtained. The effect of the VeoVa-10 and silane monomers content on the properties of the resulting emulsion lattices and their corresponding films were investigated and achieved enhanced and excellent properties. Characterization of the prepared emulsions was performed using e.g. IR, TEM, SEM, thermal analysis. The VeoVa-10 and VTMS amount has a great influence on the properties of the resulting lattices and their corresponding films. The novel waterborne poly (VeoVa-acrylate) Terpolymer latex containing silicone are characteristic of lower surface tension and better film properties such as improved thermal stability and enhanced water resistance.In addition, evaluation of the novel high solid content Nano Siliconated poly (VeoVa-acrylate) Terpolymer latex as a binder in waterborne house-hold paints was carried out. The results indicated high performance paint films with excellent physico-mechanical properties and good water and weather resistance for exterior and interior house-hold walls.

Preparation and characterization of a biodegradable polyurethane hydrogel and the hybrid gel with soy protein for 3D cell-laden bioprinting.

3D printing shows great potential for fabricating customized scaffolds for tissue regeneration. Using hydrogel as a bioink for cell printing provides a biological platform for basic research and potential medical treatments. In this study, a waterborne poly(ε-caprolactone) (PCL)-based biodegradable polyurethane (PU) with a soft segment replaced with 20 mol% of poly(l-lactide) (PLLA) diol or poly (d,l-lactide) (PDLLA) diol was prepared. These two PUs formed compact packing structures at temperatures ≥37 °C. They responded differently to temperature changes and the presence of electrolytes because of the difference in the free volume. With their thermal-responsive properties, both PU dispersions could form a gel in 3 min with the gel modulus reaching about 6-8 kPa after 30 min. To enhance the structural integrity during layer-by-layer deposition, the hybrid hydrogel of PU and soy protein isolate (PU/SPI hybrid) was further developed. The PU/SPI hybrid dispersion could undergo rapid gelation at 37 °C with the modulus reaching 130 Pa in 1 min. Moreover, the PU/SPI hybrid gel was readily blended with cells and printed at 37 °C without preheating. Neural stem cells (NSCs) were embedded in the hydrogels and analyzed for cell viability, metabolism, proliferation, and gene expression of neural-related markers. Cells cultured in the PU/SPI hybrid construct had better survival and proliferation than those in the PU gel. The PU/SPI hybrid ink may provide unique rheological properties for direct cell/tissue printing at 37 °C and a biomimetic microenvironment for cell survival, growth, and differentiation.

Synthesis and Characterization of Waterborne Poly(urethane-urea)s and Their Nanocomposites Containing Hydrophilic and Organophilic Clays

Synthesis and Characterization of Waterborne Poly(urethane-urea)s and Their Nanocomposites Containing Hydrophilic and Organophilic Clays

Simultaneous reduction and surface functionalization of graphene oxide with wrinkled structure by diethylenetriamine (DETA) and their reinforcing effects in the flexible poly(2-ethylhexyl acrylate) (P2EHA) films

NH2-reduced graphene oxide (NH2-rGO)/waterborne poly(2-ethylhexyl acrylate) (P2EHA) composites were prepared through an easy, all aqueous, electrostatic self-assembly method. GO was functionalized and reduced by diethylenetriamine (DETA) to achieve highly stable P2EHA/NH2-rGO composite colloid dispersions system, leading to the formation of composites with a self-aligned layered structure and highly anisotropic properties between the direction of alignment and that perpendicular to it. The NH2-rGO went through the structural transformation resulting in wrinkled graphene structures with many open-edge sites when N was doped into rGO sheet. The using of DETA resulted in the electrostatic interaction between the P2EHA latex and NH2-rGO and the highly aligned, ultralarged NH2-rGO sheets with surface wrinkles gave rise to the improved mechanical, electrical and thermal properties of the composites.

Synthesis and characterizations of waterborne poly(acrylate) latexes

Aqueous emulsions used as binders in solvent-free paint formulations have to cope with the challenge to guarantee an excellent film formation and appearance as well as good properties. One strategy to fulfill these contradictory requirements is the employment of pure poly(acrylate) resins synthesized by emulsion polymerization. Kinetic studies involving free radical emulsion polymerization of methyl methacrylate (MMA)- co- n-butyl acrylate (BA) are carried out, so that the effect of BA on polymerization of MMA can be interpreted. In this study, the effect of emulsifier and initiator on the kinetics of polymerization was studied. The polymers were characterized using different analytical tools. The surface tension and contact angle of latexes were also measured by varying the concentration of monomer feed ratios. The results indicated that the incorporation of comonomer enhances the properties of coating formulation of polyacrylates.

Property profile of poly(urethane urea) dispersions containing dimer fatty acid-, sugar- and amino acid-based building blocks

The understanding of the polymer composition–properties relationship is of great importance to improve the mechanical properties of bio-based polyurethanes containing long chain fatty acid derivatives. In this work, water-borne poly(urethane urea) dispersions containing dimer fatty acid-based diisocyanate (DDI), ethyl ester l-lysine diisocyanate (EELDI), 1,4:3,6-dianhydro-d-glucitol (isosorbide, IS) and dimethylolpropionic acid (DMPA) residues were prepared. The investigation focuses on the thermal and mechanical properties of these dispersion-cast films as well as on the morphology in correlation with the polymer composition. Significant dependencies of these properties and the morphology on the polymer composition are observed. By partially replacing the flexible DDI with the rigid EELDI as well as by increasing the isosorbide contents in the monomer feed, the Tg as measured by DSC was significantly enhanced from 18 to 58°C (1st Tg) and to above 70°C (2nd Tg). As evidenced from the DSC, AFM and FT-IR measurements, the H-bonds-induced micro-phase separation was influenced by the polymer composition. The observed improved phase mixing at relatively high EELDI-to-DDI ratio was related to the increased EELDI content and the corresponding urethane/urea bonds. The viscoelastic behavior of these dispersion-cast films showed a strong dependence on the ratio of the flexible DDI to the rigid EELDI and were less dependent on the IS and DMPA contents.

Interfacial interactions of poly(urethane–urea) based primers with polypropylene

Good adhesion to polypropylene is required in a number of technologies including printing, painting and food packaging technology. However, for good adhesion between polyolefins and other materials it is usually necessary to pretreat and prime the polyolefinic substrate. In this paper waterborne poly(urethane–urea)s (wPUU) were employed as primers synthesized using various chain extenders: hydrazine (HYD), ethylenediamine (EDA) and adipic acid dihydrazide (ADH). Cast films obtained from these wPUUs on biaxially-oriented polypropylene (BOPP) substrates were analyzed exploiting Infrared spectroscopy (IR) as well as Dynamic Mechanical Analysis (DMA) and T-peel tests. The type of chain extender used influences the intermolecular hydrogen bonding efficiency, the molecular ordering and the intermolecular interactions with the water molecules, thereby affecting significantly the final adhesion properties of the primer/BOPP films. Self-assembled, close-packed PUU using HYD appears to be the most efficient primer due to better phase separation driven by higher hydrogen bonding efficiency.