聚氨酯/丙烯酸酯复合乳液的制备方法及性能研究进展

介绍了近年来国内外聚氨酯/丙烯酸酯复合乳液制备方法：物理共混、种子乳液聚合法、原位聚合法等;评述了聚氨酯的结构、聚丙烯酸酯、引发剂以及制备方法等因素对复合乳液性能的影响;对目前常用的无机纳米粒子和交联等对聚氨酯/丙烯酸酯复合乳液改性方法进行了讨论;展望了该领域的发展趋势。     

Preparation and characterization of Fe‐Tetranitro phthalocyanine/polyurethane blends

In this article, Fe‐Tetranitro phthalocyanine (Fe‐TNPc)/polyurethane (PU) blends were prepared by solution blending. The mechanical properties of the samples were studied by tensile tests. The results showed that the tensile strength and the elongation at break of the samples increased with increasing Fe‐TNPc content. The improved mechanical properties for the samples containing Fe‐TNPc was attributed to the increased microphase separation degree of PU, which was further investigated by dynamic mechanical analysis (DMA) and Fourier transform infrared analysis. The lower T_g of the soft segments and the higher T_g of the hard segments for the samples containing Fe‐TNPc indicated an increase of microphase separation degree of PU. The increased hydrogen bonded carbonyl groups in the samples with increasing Fe‐TNPc content also proved the conclusion. Quantitative evaluation of the interaction between Fe‐TNPc and PU was also investigated by analyzing the physical crosslinking density of the samples. The results indicated that the physical crosslinking density of the samples increased with increasing Fe‐TNPc content. The antibacterial properties of the samples were investigated. The results showed that the percentage bacterial inactivation toward S. aureus and E. coli of the samples were 98.9% and 90.9%, respectively, when Fe‐TNPc was added to 1%. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41284.     

GMA对水性聚氨酯/聚丙烯酸酯清漆性能的影响

以聚己内酯二元醇(PCL)、异佛尔酮二异氰酸酯(IPDI)、2,2-二羟甲基丁酸(DMBA)、甲基丙烯酸甲酯(MMA)和丙烯酸丁酯(BA)为原料合成水性聚氨酯/聚丙烯酸酯乳液(WPUA),向WPUA中引入甲基丙烯酸缩水甘油酯(GMA)和烯丙氧基羟丙基磺酸钠(AHPS),制备了环氧改性水性聚氨酯/聚丙烯酸酯(EPUAS)复合乳液,采用傅里叶变换红外光谱(FTIR)、X射线衍射仪(XRD)和热重分析(TGA)对改性前后EPUAS膜的结构和性能进行了表征,探讨w(GMA)对乳液及其涂膜性能的影响。结果表明:EPUAS乳液具有核壳结构,随着w(GMA)由1%提高到4%,胶膜的热稳定性提高,分解率为10%、30%、50%的热分解温度分别提高了9.4、20.2、45.5℃,拉伸强度从6.8 MPa逐渐增加到12.3 MPa,断裂伸长率由12.2%减小到6.6%,交联度由60.1%增加到81.7%、乳液的粒径从198 nm增大到273 nm;且在w(GMA)为4%时,EPUAS胶膜的吸水率、吸溶剂率分别降到7.2%、16.3%,综合性能达到最佳。     

聚氨酯/聚丙烯酸酯复合弹性体的力学性能研究

采用预聚体法合成了一系列聚氨酯／聚丙烯酸酯复合弹性体，研究了组成比例对PU／PA复合弹性体的力学性能的影响。结果表明：聚丙烯酸甲酯的比例在一定范围内时，可以较大程度地提高材料的力学强度和断裂伸长率，而将丙烯酸甲酯和甲基丙烯酸甲酯混合加入聚氨酯中，形成的复合弹性体的力学性能无明显改善。     

Structure and property characterization of nanograde core‐shell polyurethane/polyacrylate composite emulsion

Anionic aqueous polyurethane dispersion was synthesized through self‐emulsifing method from cycloaliphatic isophorone diisocyanate (IPDI) and dimethylolpropionic acid (DMPA). The carboxyl acid group in DMPA was used to make the polyurethane dispersible. The polyurethane/polyacrylate (PU/PA) composite particles were also prepared by seeded surfactant‐free emulsion polymerization; the cycloaliphatic polyurethane aqueous dispersion was used as seed particles. The structures and properties of the composite emulsion as well as the physical mixture of polyurethane dispersion and polyacrylate emulsion were characterized by FTIR, DSC, dynamic light scattering, TEM, X‐ray photoelectron spectroscopy (ESCA), and electronic tensile machine. The results showed that the synthesized PU/PA composite emulsion was found to form inverted core‐shell structure with polyacrylate as the core and with polyurethane as the shell, and its diameter of particles is in the range of nanograde, the crosslinking reaction was existed in composite emulsion. The intimate molecular mixing of crosslinking polymers are also claims to result in a superior balance of properties compared to physical blends of polyurethane dispersion and acrylate emulsion. The crosslinking mechanism of PU/PA composite emulsion was also discussed. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Preparation and properties of halogen‐free flame‐retarded phthalonitrile–epoxy blends

Halogen‐free flame‐retarded blends composed of 2,2‐bis[4‐(3,4‐dicyanophenoxy) phenyl] propane (BAPh) and epoxy resin E‐44 (EP) were successfully prepared with 4,4′‐diaminodiphenyl sulfone as a curing additive. The structure of the copolymers was characterized by Fourier transform infrared spectroscopy, which showed that epoxy groups, a phthalocyanine ring, and a triazine ring existed. The limiting oxygen index values were over 30, and the UL‐94 rating reached V‐0 for the 20 : 80 (w/w) BAPh/EP copolymers. Differential scanning calorimetry and dynamic rheological analysis were employed to study the curing reaction behaviors of the phthalonitrile/epoxy blends. Also, the gelation time was shortened to 3 min when the prepolymerization temperature was 190°C. Thermogravimetric analysis showed that the thermal decomposition of the phthalonitrile/epoxy copolymers significantly improved with increasing BAPh content. The flexible strength of the 20:80 copolymers reached 149.5 MPa, which enhanced by 40 MPa compared to pure EP. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Preparation and physico‐mechanical,thermal and acoustic properties of flexible polyurethane foams based on hydroxytelechelic natural rubber

Novel flexible polyurethane foams were successfully prepared from a renewable source, hydroxytelechelic natural rubber (HTNR) having different molecular weights (1000–3400 g mol^?1) and variation of epoxide contents (EHTNR, 0–35% epoxidation) by a one‐shot technique. The chemical and cell structures as well as physico‐mechanical, thermal, and acoustic properties were characterized and compared with commercial polyol analogs. The obtained HTNR based foams are open cell structures with cell dimensions between 0.38 and 0.47 mm. The HTNR1000 based foam exhibits better mechanical properties but lower elongation at break than those of commercial polyol analog. However, the HTNR3400 based foam shows the best elastic properties. In a series of EHTNR based foams, the tensile and compressive strengths show a tendency to increase with increasing epoxide content and amount of 1,4‐butanediol (BD). The HTNR based foams demonstrate better low temperature flexibility than that of the foam based on commercial polyol. Moreover, the HTNR based polyurethane foams was found to be an excellent absorber of acoustics. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Starch‐based biodegradable blends: morphology and interface properties

In order to improve the properties of plasticized wheat starch (PWS) and to conserve its final biodegradability, PWS can be blended with biodegradable polyesters [polyesteramide, poly(ε‐caprolactone), poly(lactic acid), poly(butylene succinate adipate) and poly(butylene adipate terephthalate)] which exhibit variable polar characteristics. This paper is focused on the analysis of the compatibility of these blends which vary according to their formulation. To understand the lack of affinity between the different phases, interface adhesion has been investigated by contact angle measurements to obtain the work of adhesion. From these determinations a forecast approach has been developed to predict blend compatibility. Blend structures were obtained by scanning electron microscopy observations. Blends show either a dispersed structure or a co‐continuous morphology. Percolation thresholds (co‐continuity) and full continuity regions were determined thanks to a method based on solvent extraction. Finally, rheological investigations have been carried out on the different biodegradable polymers to understand better the blend structure formation during the process. Copyright © 2004 Society of Chemical Industry     

Tailored ferroelectric responses and enhanced energy density in PVDF‐based homopolymer/terpolymer blends

Blend of polymers is an effective way to tailor the ferroelectric responses and improve the energy storage properties of polymers. In this work, the microstructure and dielectric responses of the blends of poly(vinylidene fluoride) (PVDF) and poly(vinylidene fluoride‐trifluoroethylene‐chlorofluoroethylene) [P(VDF‐TrFE‐CFE)] have been studied. It is found that the addition of PVDF disturbs the crystallization process of P(VDF‐TrFE‐CFE), leading to lower crystallinity and smaller crystalline size. The aforementioned microstructure changes result in tailored ferroelectric responses. Dielectric responses show that the blend with 10 wt % PVDF achieves larger polarization response under high electric field (above 300 MV/m) due to the interfacial polarization. Because of the tailoring effect and the interfacial polarization, the blend with 10 wt % PVDF exhibits higher energy density and efficiency. Moreover, the breakdown strength (E_b) is also improved by adding a small amount of PVDF into the terpolymer. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40994.     

Temperature dependence of hydrogen bond in Fe‐OCAP/polyurethane blends

Fourier transform infrared (FTIR) thermal analysis was utilized to study the temperature dependence of hydrogen bond in Fe‐octacarboxyl acid phthalocyanine (Fe‐OCAP)/polyurethane (PU) blends. Two regions in the FTIR spectra were concerned to investigate the difference of the degree of hydrogen bond in the samples: the ? NH stretching region (3210–3460 cm^?1) and carbonyl stretching region (1680–1760 cm^?1). It was found that the average strength of hydrogen bond in the modified samples was stronger than that in pure PU. With increasing Fe‐OCAP content, the hydrogen bonded ? NH and carbonyl groups were increased, while with increasing temperature they decreased. The equilibrium between free and hydrogen bonded carbonyl groups was discussed. The dissociation enthalpy for hydrogen bonded carbonyl of the samples was increased with increasing Fe‐OCAP content. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2265–2271, 2013     

Preparation and studying properties of polybutene‐1/thermoplastic starch blends

Starch as an inexpensive and renewable source has been used as a filler for environmental friendly plastics for about two decades. In this study, glycerol was used as a plasticizer for starch to enhance the dispersion and the interfacial affinity in thermoplastic starch (TPS)/polybutene‐1(PB‐1) blend. PB‐1 was melt blended with TPS using a single screw extrusion process and molded using injection molding process to investigate the rheological and mechanical properties of these blends. Rheological properties were studied using a capillary rheometer, and the Bagley's correction was performed. Mechanical analysis (stress–strain curves) was performed using Testometric M350‐10 kN. The rheological properties showed that the melt viscosity of the blend is less than that of PB‐1, and the flow activation energy at a constant shear stress of the blend increases with increasing glycerol content in the blend. The mechanical experiments showed that both stress and strain at break of the blends are less than that of PB‐1, whereas the Young's modulus of the most blends is higher than that of PB‐1 which confirms the filling role of TPS in the blend. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Preparation and characterization of castor oil‐based polyurethane/poly(o‐methoxyaniline) blend film

Blends made up of castor oil‐based polyurethane (PU) and poly(o‐methoxyaniline) (POMA) were obtained in the form of films by casting and characterized by FTIR, UV‐Vis‐NIR spectroscopy, and electrical conductivity measurements. Doping was carried out by immersing the films in 1.0M HCl aqueous solution. Chemical bonds between NCO group of PU and NH group of POMA were observed by means of FTIR spectra. The UV‐Vis‐NIR spectra indicated that the presence of the PU in the blend does not affect doping and formation of the POMA phase. The electrical conductivity research was in the range of 10^?3 S/cm. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Synthesis and properties of polydimethylsiloxane/graphene oxide modified,water-based polyurethane/polyacrylate

In this study, we prepared polydimethylsiloxane–graphene oxide (PG) modified waterborne polyurethane acrylate (WPUA) films and enhanced their hydrophobicity, thermal stability, and mechanical properties. The prepared films were characterized by Fourier transform infrared and energy spectroscopy analysis; this confirmed the successful incorporation of PG into WPUA. As shown by scanning electron microscopy and atomic force microscopy analysis, the surfaces of the WPUA films were confirmed to have turned smoother and more compact after PG addition. With an optimized amount of PG (0.1%) incorporated into the WPUA film, it exhibited a contact angle improvement of 21.9°, an enhanced decomposition temperature at 5% weight losses of 25 °C, and an elongation at break improvement of 482.92% over those of pure WPUA. The newly synthesized PG–WPUA showed considerable enhancements in its hydrophobicity and thermal and mechanical properties and could be deemed to have potential value as an alternative contender for practical applications in coatings painted on tunnels and highways. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47926.     

Mechanical properties of uncrosslinked and crosslinked linear low‐density polyethylene/wax blends

The mechanical properties of uncrosslinked and crosslinked linear low‐density polyethylene (LLDPE)/wax blends were investigated, using differential scanning calorimetry (DSC), tensile testing, and melt flow indexing. A decrease in the degree of crystallinity, as determined from the DSC melting enthalpies, was observed with an increase in the dicumyl peroxide (DCP) concentration. The Young's modulus increased with increased wax portions, and there was a higher increase for crosslinked blends. The yield stress generally decreased with increased peroxide content. Crosslinking caused an increase in elongation at yield, but increased wax content caused a decrease in elongation at yield. The stress at break generally increased with increasing peroxide content, but it decreased with increased wax content. The elongation at break decreased with an increase in the DCP concentration. Melt flow rate measurements indicated a mutual miscibility in LLDPE/wax blends. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 973–980, 2001     

Preparation and thermal properties of bismaleimide blends based on hydroxyphenyl maleimide

N‐(4‐hydroxyphenyl)maleimide was melt‐blended with the glycidyl ether of bisphenol‐A and various mole percentages of 4, 4′‐(diaminodiphenylsulfone) bismaleimide. The cure behaviour of the resins was evaluated by differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA). The blends showed distinct reductions in the onset of cure (T_o) and peak exothermic (T_exo) temperatures. The blends cured at low temperatures exhibited glass transition temperatures (T_gs) higher than the cure temperatures. The cured blends showed high moduli, glass transition temperatures in excess of 250 °C and good thermal stabilities up to 400 °C. Copyright © 2005 Society of Chemical Industry     

氟代聚丙烯酸酯改性聚氨酯复合乳液的制备及其疏水性

为了提高聚氨酯-丙烯酸酯复合乳液的耐水性和耐溶剂性,将聚氨酯溶液作为反应介质,以丙烯酸十二氟庚酯(FA)和丙烯酸羟丙酯为单体,偶氮二异丁腈为引发剂,在溶液中进行聚丙烯酸酯自由基聚合,然后用N-甲基二乙醇胺进行亲水基扩链,通过溶液聚合相转化法制得新型阳离子氟代聚丙烯酸酯改性聚氨酯复合乳液。通过红外光谱、透射电镜、光电子能谱仪和接触角测定仪分别对复合乳液的结构、乳胶粒形态、膜表面的化学元素组成及疏水性进行了研究。结果表明,含氟链段成功接入了大分子链中,乳液形成稳定的核-壳结构,在膜材料表面形成了主要由含氟丙烯酸酯链段组成的界面,FA的引入可使复合乳液胶膜与水的接触角(PUA膜与水的接触角)由65°提高至98°。     

Preparation,mechanical properties of waterborne polyurethane and crosslinked polyurethane‐acrylate composite

The waterborne polyurethane (PU) prepolymer was first prepared based on isophorone diisocyanate, polyether polyol (NJ‐210), dimethylol propionic acid (DMPA), and hydroxyethyl methyl acrylate via in situ method. The crosslinked waterborne polyurethane‐acrylate (PUA) dispersions were prepared with the different functional crosslinkers. The chemical structures, optical transparency, and thermal properties of PU and PUA were confirmed by Fourier transform infrared spectrometry, ultraviolet–visible spectrophotometry, and differential scanning calorimetry. Some physical properties of the aqueous dispersions such as viscosity, particle size, and surface tension were measured. Some mechanical performances and solvent resistance of PUA films were systemically investigated. The experimental results showed that the particle sizes of the crosslinked PUA aqueous dispersions were larger than the PU and increased from 57.3 to 254.4 nm. When the ratios of BA/St, BA/TPGDA, and BA/TMPTA were 70/30, PUA films exhibited excellent comprehensive mechanical properties. The tensile strength and elongation at break of the film were 2.17 MPa and 197.19%. When the ratio of BA/St was 30/70, the film had excellent water resistance and was only 6.47%. The obtained PUA composites have great potential application such as coatings, leather finishing, adhesives, sealants, plastic coatings, and wood finishes. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

The study of palm‐oil‐based bio‐polyol on the morphological,acoustic and mechanical properties of flexible polyurethane foams

The focus of this paper was to explore the acoustic properties of flexible polyurethane (FPU) foam modified by palm‐oil‐based polyol (POP). The presence of POP showed a marked influence on the microstructure and mechanical properties of FPU foam. A smaller mean pore diameter can be observed at lower POP content. Indeed, the introduction of POP caused a higher closed pore ratio and an increased air‐flow resistivity, which consequently improved the sound absorption coefficient and transmission loss. In particular, the acoustic performance of the all bio‐based FPU foam was enhanced at low frequency, and the density was lower than that of the reference foam. Additionally, the addition of POP also improved the compressive strength. Conversely, the tensile strength of FPU foam declined with increasing POP content. From this study, the outstanding acoustic ability of bio‐based FPU foam has been proved, with additional advantages of lower density and higher compressive strength. © 2019 Society of Chemical Industry     

Effect of dynamic cross‐linking on melt rheological properties of polypropylene/ethylene‐propylene‐diene rubber blends

Study of melts rheological properties of unvulcanized and dynamically vulcanized polypropylene (PP)/ethylene‐propylene‐diene rubber (EPDM) blends, at blending ratios 10–40 wt %, EPDM, are reported. Blends were prepared by melt mixing in an internal mixer at 190°C and rheological parameters have been evaluated at 220°C by single screw capillary rheometer. Vulcanization was performed with dimethylol phenolic resin. The effects of (i) blend composition; (ii) shear rate or shear stress on melt viscosity; (iii) shear sensitivity and flow characteristics at processing shear; (iv) melt elasticity of the extrudate; and (v) dynamic cross‐linking effect on the processing characteristics of the blends were studied. The melt viscosity increases with increasing EPDM concentration and decreased with increasing intensity of the shear mixing for all compositions. In comparison to the unvulcanized blends, dynamically vulcanized blends display highly pseudoplastic behavior provides unique processing characteristics that enable to perform well in both injection molding and extusion. The high viscosity at low shear rate provides the integrity of the extrudate during extrusion, and the low viscosity at high shear rate enables low injection pressure and less injection time. The low die‐swell characteristics of vulcanizate blends also give high precision for dimensional control during extrusion. The property differences for vulcanizate blends have also been explained in the light of differences in the morphology developed. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 1488–1505, 2000     

Polystyrene and polyether polyurethane elastomer blends compatibilized by SMA: Morphology and mechanical properties

Blends of polystyrene (PS) and the polyether polyurethane elastomer (PU‐et) were prepared by melt mixing using poly(styrene‐co‐maleic anhydride) (SMA) containing 7 wt % of maleic anhydride as a compatibilizer. The polyurethane in the blends was crosslinked using dicumyl peroxide or sulfur. The content of maleic anhydride was varied in the blends through the addition of different SMA amounts. The morphology of the blends was analyzed by SEM and a drastic reduction of both the domain size and its distribution was observed with increase of the anhydride content in the blends. The morphology of the PU‐et blends also showed dependence on the crosslinker agent used for the elastomer, and larger domains were obtained for the elastomer phase crosslinked with dicumyl peroxide. The mechanical properties of the blends were evaluated by flexural and impact strength tests. The blend containing 0.5 wt % of maleic anhydride and 20 wt % of PU‐et crosslinked with sulfur showed the highest strength impact, which was three times superior to the PS strength impact, and the blends containing 20 wt % of PU‐et crosslinked with dicumyl peroxide showed the highest deflection at break independent of the anhydride content. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 830–837, 2002