In this paper, a series of tetrameric surfactants (4CnSAZs, n = 12, 14, 16) endowed with zwitterionic characteristic were synthesized by a simple and convenient method and their structures were characterized by FT-IR, 1H NMR and elemental analysis. Their physicochemical properties were studied using the Wilhelmy plate method, fluorescence spectra and dynamic light scattering technique. 4CnSAZs have higher surface activities and tend to adsorb at the air/water surface rather than self-assembling in aqueous solution. The thermodynamic parameters obtained from surface tension measurements show that both processes of adsorption and micellization of 4CnSAZs are spontaneous and that the micellization processes of 4CnSAZs are entropy-driven processes. Both adsorption and micellization of 4CnSAZs are inclined to occur with the increase of alkyl chain length or temperature. For 4C12SAZs, there are only small-size aggregates (micelles), while the large aggregates (vesicles) are observed at the alkyl length of 4CnSAZs of 14 or 16. This shows that the alkyl chain length for oligomeric surfactants has a greater sensitivity for aggregate growth. The aggregate morphologies obtained from the calculated values of critical packing parameter (p) for 4C14SAZs and 4C16SAZs can be supported by the DLS measurement results. The test results obtained by the separation-water-time method show that 4CnSAZs have good emulsification performance and that the prepared emulsions appear to exit in the form of multiple emulsions. In addition, 4CnSAZs have good antibacterial activities against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The present study reveals the unique behavior of a zwitterionic tetrameric surfactant and may give new insights into molecular design and synthesis of a high degree of surfactants with different structure characteristics for potential application in various industrial fields.

Hydroxyl-terminated polybutadiene (HTPB) is a flexible telechelic compound with a main chain containing a slightly cross-linked activated carbon-carbon double bond and a hydroxyl group at the end. Therefore, in this paper, HTPB was used as a terminal diol prepolymer, and sulfonate AAS and carboxylic acid DMPA were used as hydrophilic chain extenders to prepare low-temperature adaptive self-matting waterborne polyurethane (WPU). Due to the fact that the non-polar butene chain in the HTPB prepolymer cannot form a hydrogen bond with the urethane group, and the solubility parameter difference between the hard segment formed by the urethane group is large, the gap of Tg between the soft and hard segments of the WPU increases by nearly 10 °C, with more obvious microphase separation. At the same time, by adjusting the HTPB content, WPU emulsions with different particle sizes can be obtained, thereby obtaining WPU emulsions with good extinction properties and mechanical properties. The results show that HTPB-based WPU with a certain degree of microphase separation and roughness obtained by introducing a large number of non-polar carbon chains has good extinction ability, and the 60° glossiness can be as low as 0.4 GU. Meanwhile, the introduction of HTPB can improve the mechanical properties and low temperature flexibility of WPU. The Tg,s (the glass transition temperature of soft segment) of WPU modified by the HTPB block decreased by 5.82 °C, and the ΔTg increased by 21.04 °C, indicating that the degree of microphase separation increased. At -50 °C, the elongation at break and tensile strength of WPU modified by HTPB can still maintain 785.2% and 76.7 MPa, which are 1.82 times and 2.91 times those of WPU with only PTMG as soft segment, respectively. The self-matting WPU coating prepared in this paper can meet the requirements of severe cold weather and has potential application prospects in the field of finishing.

Ultrathin two-dimensional (2D) nanosheets have driven the development of multifunctional materials. However, persistent challenges with complex processes, low production rates, and high costs have prevented ultrathin 2D nanosheets from realizing their full potential in nanocomposite. Herein, large-scale exfoliated montmorillonite (MTM) mono-layered nanosheets in polyethyl-phosphate glycol ester were assembled into environment-friendly waterborne polyurethane to obtain multifunctional nanocoatings with superior matte performance, favorable flame retardancy, and high adhesion. Specifically, a significant 98.2 % decrease of 60 degrees gloss from 65.0 GU to 1.2 GU was observed, which almost wholly diffuses incident light due to the rougher surface. Besides, total heat release and total smoke rate were decreased by a maximum of 27.1 % and 34.4 %, respectively. Surprisingly, the nanocoating with excellent anti-blocking properties has outstanding adhesion to PU leather. These nanocoatings on leather and fabric showed potential for engineering applications. This study may provide new insight for application of ultrathin 2D nanosheets in multifunctional materials.

As increasing attention is being paid to harmful residual dye pollution in the dyeing effluent from the microfiber synthetic leather industry, there is an urgent need to explore innovative ways to alleviate such pollution. Here, a low-polarity waterborne polyurethane (WPU) was synthesized using hydroxyl-terminated polybutadiene (HTPB) and polypropylene glycol (N220) as soft segments to react with –NCO on isophorone diisocyanate (IPDI). The structure and properties of modified waterborne polyurethane were characterized by Fourier Transform Interferometric Radiometer (FTIR), and emulsion characterization was performed, including particle size and zeta potential analysis, tensile test, thermal properties test, and contact angle test. The SEM and alkali reduction rate results showed that increasing the HTPB content decreases the alkali reduction rate by blocking the penetration of corrosive ions by the double bond cross-link structure, but higher HTPB addition (>40%) leads to an enhancement in phase separation, which contributes to an increase in the alkali reduction rate. The results of the UV spectrum analysis showed that when the amount of HTPB added was 50%, the coloration rate reached 81.27% compared with 13.18%, which was 68.09% higher than that of the unmodified microfiber leather. The binding of the dry and wet rubbing color of the modified microfiber leather with the addition of 50% HTPB reached grades of 4–5 and 3–4, respectively, which meets most application requirements without subsequent washing.

采用端羟基聚丁二烯(HTPB)剥离层状有机蒙脱土(OMMT)为纳米片,并与异佛尔酮二异氰酸酯(IPDI)、二羟甲基丙酸(DMPA)等单体通过原位聚合法制备了OMMT纳米片改性的水性聚氨酯(OMMT/WPU)纳米乳液.利用小角XRD、TEM、DLS、EDS、TGA、SEM、锥形量热及极限氧指数测定方法对样品的结构和性能进行了表征.结果表明,HTPB剥离的OMMT纳米片的衬度均匀,完整性较好;改性后OMMT/WPU乳液的粒径增大,胶膜的弹性模量、热稳定性、抗熔滴性和阻燃性能均得到明显改善,其中弹性模量可提高约59.4％,热释放速率峰值可降低约36.9％;燃烧炭渣表面形貌显示,瓦片状蒙脱土相互穿插形成了具有团簇结构的蒙脱土覆盖层.

With the change of people's aesthetic concepts, low-gloss coatings are becoming a new hotspot of interest. However, the low-gloss waterborne polyurethane (WPU) coatings reported by others to our knowledge are all single-functional coatings, which are difficult to meet the requirements of complex application environments. Herein, a series of low-gloss WPU nanocoatings with versatility via mono-layered organic montmorillonite (OMt) nanosheets is reported, and then applied to polyester fabric. Ultraviolet-visible (UV–vis) examination indicated that the OMt nanosheets made the as-prepared nanocoatings have unique UV-shielding performance. Thermogravimetric analysis (TGA) curves showed that the OMt nanosheets increased the thermal stability of the nanocoatings. Moreover, Fourier transforms infrared (FTIR) spectroscopy confirmed the existence of hydrogen bonds between OMt nanosheets and WPU molecular chains, which is the essential reason why the nanocoating had a matte level of 60° gloss of 1.9 GU on the fabric. Rougher surface topography of the nanocoating compared with pristine WPU coating and fabric observed by scanning electron microscopy (SEM) is the direct reason for the decrease in gloss. In addition, the influence of the times of scraping on the gloss of the coatings was also studied. Thus, our research may provide new insights for the multifunctional matte WPU coatings.

Polyurethane elastomers are a commercial success because of their broad range of properties, low cost, and ease of production. Nonetheless, developing new, less expensive polyurethane elastomers with improved or expanded properties is an important goal. Since hard domains dominate the physical properties of these polymers, we have investigated methods to disrupt hard domain formation. The use of multiple chain extenders was envisioned to inhibit hard domain formation by disrupting the alignment between hard segments. In MDI-based polyurethanes, we observed up to a one magnitude reduction in tensile modulus and a significant increase in elongation compared to polymers containing a single chain extender. The stress relaxation of these polymers containing mixed chain extenders is lower than the control polymers, and there was no loss of high temperature properties when multiple chain extenders were used. Furthermore, as the mole fraction of either of the two chain extenders is increased from 0.5, the properties of the resultant polymer approach those of the polymer with that particular pure chain extender. Polymers containing TDI or HDI as isocyanate do not have such a dramatic drop in modulus when multiple chain extenders are used. HDI polymers are too strongly phase separated to significantly alter the morphology. TDI polymers produced with a strongly hydrophilic soft segment are not phase separated, while in less polar polyols the two isomers in TDI may effectively disrupt hard domain formation independently of the chain extenders. Nonetheless this technology is a simple and cost effective method for tailoring MDI-based polymers' properties over a wide range by only minimally changing the formulation.

A series of self-matting waterborne polyurethanes (WPUs) were successfully prepared by introducing hydrophilic units into both soft and hard segments. By employing a polycaprolactone polyol containing carboxylate groups within the polymer chains to provide hydrophilicity directly, the matting performance of WPU films was greatly improved. The chemical structures of the WPU resins were confirmed by FTIR spectroscopy, and the morphology of WPU films was observed by SEM. The parameters of WPU preparation were investigated in detail. It was found that the surface gloss of WPU films as well as the particle sizes of WPU dispersions were closely associated with the content of hydrophilic units. As the content of carboxylates or sulfonates increased, the particle sizes of WPU decreased, while the gloss increased gradually. When the particle sizes of dispersions were greater than 3 μm, the gloss of WPU films coated on a leather surface was lower than 1. The results of TG showed that, the initial decomposition temperatures of WPU films were higher than 280 °C, which indicated these films also had good thermal stability. The prepared self-matting WPU coatings would have potential application prospects in the field of leather finishing.

Recently, covalent adaptable networks (CANs) based on dynamic exchange reactions have been synthesized, and the research on these materials has been mainly focused on the self-healing behavior and reprocessing properties of CANs. Disulfide bonds can be considered to be a type of dynamic reversible covalent bonds, and exchange reactions of disulfide bonds proceed easily at mild temperatures, which endow materials containing disulfide bonds with self-healing properties and the reprocessability under suitable conditions. Herein, we synthesized a type of waterborne polyurethane (WPU) CAN incorporated with disulfide bonds. A reasonable structural design was used in conjunction with a self-healing kinetic analysis to predict that the highest performing CWPU-8 sample could repair a microcrack at room temperature, which was verified by optical microscopy observations combined with self-healing mechanics. The most important feature of this material is its reprocessing property, which was investigated by rheology tests. These assessments demonstrate that the self-healing behavior and the reprocessability are closely related to exchange reactions of disulfide bonds, and the structure-property relationship provides deep insights into the CANs chemistry.

A large-scale exfoliation method to obtain high-quality and mono-layered montmorillonite (Mt) nanosheets via the aggregation of polyethyl-phosphate glycol ester (Exolit OP 550) was proposed. Small-angle X-ray diffraction (XRD), transmission electron microscope (TEM), selected area electron diffraction (SAED), and atomic force microscopy (AFM) examinations indicated that 30.0 wt.% of layered Mt. were exfoliated into mono-layered nanosheets in Exolit OP 550 after a mechanical stirring process at 60 degrees C for 12 h. This exfoliation concentration was increased by 67-650% compared with that of other works. The Mt. nanosheets with Exolit OP 550 were then assembled into environment-friendly waterborne polyurethane (OPWPU) coating by in situ polymerization. A significant decrease of 60 degrees gloss, from 30.2 GU to 0.3 GU, was observed. Many large, uniform, and continuous spherical particles on the surface of OPWPU nanocoatings were found by scanning electron microscopy (SEM), which resulted in a rough surface that almost completely diffused incident light. Besides, limiting oxygen index (LOI), cone calorimeter testing (CCT), and SEM results suggested that the OPWPU nanocomposites also had improved fire retardancy, especially the peak heat release rate was decreased by a maximum of 39.2%. This study may open up new possibilities for the application of Mt. nanosheets in polymers.

A series of low gloss organic montmorillonite/waterborne polyurethane nanocomposite (OWPU) coatings with polycaprolactone (PCL) and hydroxyl terminated polybutadiene (HTPB) were prepared, characterized and then applied to polyvinyl chloride leather. Small-angle XRD and TEM examinations indicated that montmorillonite was exfoliated into individual single-layer nanosheets in HTPB, and retained separate shapes in subsequent synthesis and preparation. The OWPU dispersions with higher nanosheets contents exhibited a larger average particle size and a less negative zeta potential obtained through DLS. A rougher coating surface topography of OWPU compared with pristine WPU was observed by SEM, which reduced the 60 degrees gloss to 4.6 GU within the matt range. Moreover, TGA results indicated that the nanosheets effectively increased thermal stability of hard segments and soft segments derived from PCL, but had little effect on that of soft segments derived from HTPB. Furthermore, rheological analysis confirmed the nanosheets promoted cross-linking and cyclization of HTPB at high temperature, thereby imparting anti-dripping properties to OWPU coatings. Cone calorimeter test and SEM results showed that flame retardancy of OWPU was improved by forming a charred layer with sheet-cluster structure. In addition, incorporation of the nanosheets was also capable of changing the surface touch feeling of OWPU coatings from sticky to some dry alike.

In order to improve the stability of waterborne polyurethane fixative during the color-fixing treatment, a novel environment-friendly cationic waterborne polyurethane (CWPU) containing quaternary ammonium groups was synthesized from isophorone diisocyanate, polypropylene glycol, butanone oxime, and N-methyl dihydroxyethyl allyl ammonium chloride (MDAAC) and dispersed in water by using diethylenetriamine as the post-chain extender. The structures of the MDAAC and CWPU were characterized by 1H-NMR and FTIR. Effects of R-value, MDAAC content, post-chain extender and blocking agent on the properties of the waterborne polyurethane emulsion and the rubbing fastness of the treated dyed cotton fabrics were investigated. The investigation results showed that the R-value and the cationic group content of the cationic waterborne polyurethane had no significant effect on the color-fixing performance, but the content of DETA had a great influence on the wet-rubbing fastness. The wet rubbing fastness of the treated cotton fabrics was promoted from grade 1-2 to grade 3. Furthermore, the quaternary ammonium groups were able to provide the surface charges for the stabilization of the resulting polymer in alkaline electrolyte solution which met the requirements of practical applications.

Hyperbranched polyesters were modified by acrylic acid,so that the hydroxyl end groups translated into double bonds.And raw materials and products were characterized by infrared spectroscopy and nuclear magnetic resonance(NMR),the results showed the end-group translated into double bond,it means unsaturated hyperbranched polyester was synthesised.Useing NMR peak area,conversion was calculated,the conversion of different generation hyperbranched polyester were all above 90%.The unsaturated hyperbranched polyester may be used as crosslinking agent of free radical reactions and light curing materials.

An aliphatic type of Hyperbranched Polyester(HBPE) was synthesized from 2,2-dihydroxymethyl propanyl acid(DMPA) and 1,1,1-trihydroxymethyl propane(TMP) via Pseudo-One-Step method,and employed to improve the pervaporation properties of Ethyl Cellulose(EC) membrane on Benzene/Cyclohexane separation.The permeate flux of membrane was enhanced greatly with the similar separation factor,when moderate amount of HBPE was added into EC membrane.The sorption properties of EC-HBPE and EC membranes were investigated.The results indicate that,the sorption selectivity of EC membrane dosn′t changed significantly,but the sorption amount at equilibrium for EC-HBPE is elevated in the case of the content of G4HBPE in EC is 20%(mass fraction),and all membranes show more preferential toward Benzene than Cyclohexane.The total permeate flux of EC-G4HBPE membrane increases from 14 kg/um·m2·h of EC to 34 kg/um·m2·h,and the separation factor from 3.25 of EC to 3.73 for a binary mixture containing 10% Benzene at 40 ℃.