Synthesis of Organic-Inorganic Hybrid Aluminum Hypophosphite Microspheres Flame Retardant and Its Flame Retardant Research on Thermoplastic Polyurethane

Aluminum hypophosphite microspheres(AHP) were synthesized by hydrothermal method using NaH2PO2·H2O and AlCl3·6H2O as raw materials, and then the AHP microspheres were polymerized by surface polymerization of micro-nanospheres with cyclic cross-linked poly(cyclotriphosphazene-co-4,4'-sulfonyldiphenol)(PZS). A new organic-inorganic poly(phosphonitrile)-modified aluminum hypophosphite microspheres(PZS-AHP) were synthesized by encapsulation and applied to flame retardant thermoplastic polyurethane(TPU). The microstructure and chemical composition of the PZS-AHP microsphere were characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and X-ray spectroscopy. The thermal stability of PZS-AHP microsphere was explored with thermogravimetric analysis. Thermogravimetric data indicate that the PZS-AHP microspheres have excellent thermal stability. The thermal and flame-retarding properties of the TPU composites were evaluated by thermogravimetric(TG), limited oxygen index tests(LOI), and cone calorimeter test(CCT). The TPU composite achieved vertical burning(UL-94) V-0 grade and LOI value reached 29.2% when 10 wt% PZS-AHP was incorporated. Compared with those of pure TPU, the peak heat release rate(pHRR) and total heat release(THR) of TPU/10%PZS-AHP decreased by 82.2% and 42.5%, respectively. The results of CCT indicated that PZS-AHP microsphere could improve the flame retardancy of TPU composites.

中空玻璃微球/TPU复合泡沫的制备及微孔结构的研究

目的探讨GB含量变化对中空玻璃微球/TPU复合材料相变行为、流变性能及热力学性能的影响,并研究微米尺寸填料GB对泡沫微孔形态、尺寸分布的影响。方法以中空玻璃微球和热塑性聚氨酯为原料,采用微孔注塑成型(MIM)发泡方式,制备GB/TPU复合泡沫材料。结果通过向TPU中引入微米玻璃球相改善发泡材料的微孔结构,在TPU中加入有机改性的GB,GB作为成核剂能显著提高TPU发泡材料的微孔结构。当GB质量分数为0.5%时,TPU熔体黏度得到提高,发泡性能得到改善,成功制备出具有复孔结构的GB/TPU复合泡沫。GB/TPU复合泡沫的密度被降低至0.51 g/cm3。由于微米尺寸填料GB的平均直径为18μm,与TPU熔体形成较大的相界面,因此引起泡孔尺寸较大且泡孔开孔率较高的现象。结论差示扫描量热仪(DSC)测试结果表明,在冷却阶段及第二次加热熔融阶段,GB对TPU软段相和硬段相的相变行为没有明显的影响。但是在DSC第一次加热熔融阶段,GB引起了TPU熔融峰向低温区移动。旋转流变仪测试分析结果表明,在高剪切频率下,GB/TPU复合材料的复合黏度和储能模量明显高于TPU纯料的,且TPUGB0.5(含质量分数为0.5%的GB)的复合黏度和储能模量最大。TGA结果显示,热稳定性提高,利用扫描电子显微镜(SEM)观察复合材料泡沫材料泡孔结构可知,泡孔分布和尺寸均匀性显著提高。

超临界CO_(2)制备TPU/SiO_(2)复合泡沫及其性能研究

采用热塑性聚氨酯弹性体(TPU)作为基体,纳米二氧化硅(SiO_(2))充当填料,超临界二氧化碳(scCO_(2))为发泡剂,通过简单的物理共混的方式以及scCO_(2)发泡设备制备了TPU/SiO_(2)复合发泡材料;探究了不同SiO_(2)含量对复合发泡材料的影响.结果表明,纳米SiO_(2)粒子在TPU基体中有良好的分散性,所制备的TPU/SiO_(2)复合发泡材料混合均匀;纳米SiO_(2)粒子的添加调控了复合材料的发泡行为,使其泡孔尺寸稳定、分布范围从60~180μm下降至20~40μm.SiO_(2)粒子有效提高了TPU基体的结晶性,从而使得回弹从40上升至42,硬度从45.3 Shore C上升至54.38 Shore C;抗张强度从1.18 MPa上升至4.19 MPa,断裂伸长率从237.25%上升至460.03%.

Improving the Compatibility of Biodegradable Poly (Lactic Acid) Toughening with Thermoplastic Polyurethane (TPU) and Compatibilized Meltblown Nonwoven

Poly (Lactic Acid) (PLA) is a biodegradable polymer which originates from natural resources such as corn and starch, offering excellent strength, biodegradability, nevertheless its inherent brittleness and low impact resistance properties have limited its application. On the other hand, Thermoplastic Polyurethane (TPU) has high toughness, durability and flexibility, which is one of the most potential alternatives for enhancing the flexibility and mechanical strength of Poly (Lactic Acid) (PLA) by blending it with a compatibilizer. With the aim to improve the mechanical and thermal properties of Poly (Lactic Acid) (PLA) meltblown nonwovens, The Thermoplastic Polyurethane (TPU) was melt blended with Poly (Lactic Acid) (PLA) at the different corresponding proportions for toughening the Poly (Lactic Acid) and the corresponding PLA/TPU MBs (meltblown nonwovens) were also manufactured. Joncryl ADR 4400 is mixed into the PLA matrix during processing. It was found that Joncryl had a much higher chain extension that substantially increased the molecular weight of the PLA matrix. SEM study revealed that Joncryl ADR 4400 is a good compatibilizer. Moreover, in this study, the crystallization, thermal and rheological behaviors of the corresponding PLA and TPU blends were also investigated. PLA/TPU MBs were also characterized by morphology and mechanical properties. The rheological property of the PLA/TPU meltblown nonwoven revealed that the viscosity is increasing as the amount of TPU is increasing in the blend, PLA/TPU meltblown nonwovens exhibited excellent mechanical properties;they are soft, elastic, and have certain tensile strength. New materials have potential applications in the medical and agricultural fields. Joncryl ADR 4400 compatibilized blends showed higher strength than simple PLA/TPU blends at the same PLA/TPU ratio.

PVC/TPU共混材料静动态力学性能及本构模型研究

利用万能材料试验机和高速拉伸试验机对2种成型方式和6种共混比的聚氯乙烯/热塑性聚氨酯(PVC/TPU)共混材料开展静动态拉伸力学性能测试,并基于断裂伸长率和邵氏硬度进行成型方式和共混比优选。进一步获取了共混材料在较宽应变率范围(0.001~700 s-1)的应力⁃应变数据,并进行了拉伸断面的微观表征。结果表明,模压成型材料断裂伸长率更高,共混比为90/10时材料具有最高的断裂伸长率,邵氏硬度符合试验假人软组织材料的硬度范围(邵尔40~70 A)。共混比为90/10(PVC/TPU)材料在静动态载荷下均具有显著的应变率效应。选取朱⁃王⁃唐(ZWT)方程和Sherwood⁃Frost方程构建了材料的本构模型,对比发现Sherwood⁃Frost方程拟合效果更好。形貌分析发现,静动态加载下,材料均为典型的脆性断裂,未出现明显的相分离现象。随着应变率的增加,断面逐渐变粗糙,并产生空穴及微小裂纹。

环氧大豆油反应增容对PLA/TPU共混物性能的影响

以热塑性聚氨酯(TPU)为增韧剂、环氧大豆油(ESO)为反应型相容剂,采用熔融共混制备了PLA/TPU/ESO复合材料,研究了ESO的含量对复合材料性能的影响。利用傅里叶红外光谱分析(FTIR)、力学性能测试、差示扫描量热仪(DSC)、热重分析(TGA)、动态力学性能分析(DMTA)、扫描电子显微镜(SEM)进行测试,结果表明,加入ESO后,PLA/TPU共混物的力学性能显著提升,其中,84PLA/10TPU/6ESO复合材料的综合性能最佳,与纯PLA相比,其断裂伸长率和冲击强度分别提升了32倍和8倍,拉伸强度下降了20%,但是,韧性较高,这是由于,ESO与PLA/TPU发生反应,形成PLA-g-TPU共聚物,充当PLA和TPU界面之间的桥梁,提高了PLA与TPU的相容性。

基于改性竹粉/TPU复合发泡材料的制备及其发泡行为研究

以热塑性聚氨酯(TPU)为主基体,改性竹粉为填料,采用超临界发泡技术制备了鞋用TPU复合发泡材料。研究了不同改性竹粉含量对复合发泡材料形貌结构、热稳定性、熔体流动性、密度、发泡倍率的影响。结果表明,当添加改性竹粉后,复合发泡材料的微观泡孔形貌特征为闭孔结构;随着竹粉添加量的增加,并泡情况减少,孔径逐渐减小并逐渐趋于均一;在一定范围内,随着改性竹粉添加量的增加,复合材料的起始分解温度不变,熔点降低,熔融指数呈现上升趋势;当改性竹粉的添加量为5 phr时,复合发泡材料的密度最轻且达到0151 g/cm3,发泡倍率最大且达到855。

聚氨酯类化合物包覆聚磷酸铵及其在TPU中的应用

为得到兼具良好阻燃性能和力学性能的阻燃热塑性聚氨酯(PUR)弹性体复合材料,采用原位包覆的方式制备了三种不同的PUR类化合物包覆的聚磷酸铵(APP),并将其分别添加到热塑性聚氨酯弹性体(TPU)中。研究了不同的PUR类化合物包覆后APP的亲疏水性以及对TPU/APP复合材料阻燃性能和力学性能的影响。研究结果表明,经过二苯基甲烷二异氰酸酯(MDI),PUR以及含硅PUR(SiPU)包覆后,获得的三种MDIAPP,PUAPP和SiPUAPP都从亲水性变为了疏水性,水接触角分别为128°,134°和138°,这有利于APP的储存和运输。TPU/APP复合材料的阻燃性能和力学性能测试结果表明,仅有PUAPP可以使TPU的阻燃性能和力学性能同时提高。TPU/5PUAPP的拉伸强度为27.2 MPa,较TPU/5APP提高了6.7%,而断裂伸长率为672.0%,较TPU/5APP提高了4.8%。TPU/5PUAPP的极限氧指数值从TPU/5APP的26.5%提高到了27.1%,并能通过UL 94垂直燃烧测试V-0级,没有滴落;此外,热释放速率峰值、总热释放量以及总生烟量分别较TPU/5APP降低了43.2%,22.8%和41.1%。

耐化学抗菌改性PC/TPU共混合金的制备及性能研究

以聚碳酸酯(PC)、热塑性聚氨酯弹性体(TPU)和抗菌剂为主要原料,利用熔融共混法制备了耐化学抗菌改性PC/TPU共混合金。系统地研究了TPU含量、硬度、类型和抗菌剂种类对材料性能的影响。结果表明,PC/TPU共混合金的加工流动性、缺口冲击强度及耐化学性能随TPU含量增大而提高。与聚醚型TPU相比,硬度更高的聚酯型TPU更有利于提高材料的缺口冲击韧性和化学稳定性。当加入0.6%活性氧化锌时,PC/TPU共混合金对大肠杆菌和金黄色葡萄球菌的抗菌率大于99.9%。

Physical and damping properties of kenaf fibre filled natural rubber/thermoplastic polyurethane composites

The paper presents the investigation of the effect of alkaline treatment of sodium hydroxide(NaOH) on physical and dynamic mechanical analysis(DMA) viscoelastic properties of kenaf fibre filled natural rubber(NR)/thermoplastic polyurethane(TPU) composites.The treated kenaf fiber,NR and TPU were weighed and proportioned according to the required compositions and were blended using hot mixed Brabender machine.The polymer composites were then fabricated using the hot press to form a sample board.The sample was cut and prepared and water absorption,density,thickness swelling and DMA tests were performed.As far as physical properties are concerned,composites with the highest NR amount of shows the best results,which indicates good fiber bonding adhesion.The polymer composites with the highest amount of TPU shows the highest damping properties at high temperature.

漆酚改性凹凸棒石载铜抗菌剂制备及在TPU中应用

以酸活化凹凸棒石为载体,漆酚为表面修饰剂,CuCl_(2)为铜离子源,制备了凹凸棒石载铜抗菌剂,并通过熔融共混挤出制备了抗菌热塑性弹性体(TPU)材料。着重研究了漆酚改性对凹凸棒石Cu^(2+)载量的提升作用,以及漆酚改性前后凹凸棒石负载Cu^(2+)抗菌剂对TPU物理性能和抗菌性能的影响。结果表明,漆酚的配位作用有效提升了凹凸棒石载铜能力,漆酚改性后凹凸棒石载铜负载量从13.7 mg/g提升至45.6 mg/g。漆酚与TPU基体有良好的相容性,漆酚改性的凹凸棒石载铜抗菌剂在TPU基体中呈良好分散性,在赋予TPU优异抗菌性能的同时可以有效提升材料的拉伸强度。添加1%漆酚改性凹凸棒石载铜抗菌剂时,对大肠杆菌和金黄色葡萄球菌的抑菌率均为100%,材料的拉伸强度从34.14 MPa提升至43.27 MPa。

溶液共混中TPU/PA12相容性的研究

本研究采用了不同温度下溶液共混的方式研究热塑性聚氨酯(TPU)与聚酰胺12(PA12)的相容性,通过差示扫描量热(DSC)、调制模式下的差示扫描量热(MDSC)、衰减全反射傅里叶变换红外光谱分析(ATR-FTIR)等进行相结构表征。结果表明,PA12引入能够破坏TPU硬段相的聚集结构,同时又能够有效“屏蔽”TPU软硬段之间的相互作用;计算机辅助模拟的计算结果也进一步证明了这一猜想。同时发现,150℃的温度下,TPU与PA12之间具有更好的相容性,这是因为在此温度下,接近TPU的熔点,TPU的硬段很大程度地被破坏,PA12的引入让体系中的氢键发生了重排,促进了二者之间的相容。

Effect of microwave treatment on tensile properties of sugar palm fibre reinforced thermoplastic polyurethane composites

The effect of microwave treatment on the tensile properties of treated sugar palm fibre with 6% NaOH reinforced thermoplastic polyurethane composites was investigated. Firstly, the sugar palm fibres were treated by 6% alkali solution. Then, microwave treatment was used to treat the alkali treated sugar palm fibres. Three types of temperatures(i.e. 70, 80 and 90℃) were applied in microwave treatment. The extruder and hot press machines were used to mixing the sugar palm fibres and polyurethane resin, and fabricate the composites. Tensile properties(i.e. tensile strength, tensile modulus and elongation at break) were studied by following the ASTM D-638 standard. The highest tensile strength was recorded 18.42 MPa with microwave temperature at 70℃ and 6% alkali pre-treatment. Therefore, the temperature 70℃ of microwave treatment may consider the best degree cent grate.

Synthesis and Properties of Non-isocyanate Crystallizable Aliphatic Thermoplastic Polyurethanes

A simple non-isocyanate route synthesizing thermoplastic polyurethanes（TPUs） with good thermal and mechanical properties is described. Melt transurethane polycondensation of dimethyl 1,6-hexamethylene dicarbamate with 1,4-butanediol and 1,6-hexanediol was conducted at different molar ratios under the catalysis of tetrabutyl titanate. A series of crystallizable non-isocyanate TPUs with high molecular weight were prepared. The TPUs were characterized by gel permeation chromatography, FT-IR, 1 H-NMR, differential scanning calorimetry, thermogravimetric analysis, wide angle X-ray diffraction, AFM, and tensile tests. The TPUs exhibited Mn ranging from 12 500 to 26 400 g/mol, Mw from 16 700 to 56 400 g/mol, Tm up to 151.4 °C, and initial decomposition temperature over 241.8 °C. Their tensile strength reached 42.99 MPa with a strain at break of 30.00%. TPUs constructed simply with butylene, hexylene, and urethane linkages were successfully synthesized through a non-isocyanate route.

Effect of Accelerated Xenon Lamp Aging on the Mechanical Properties and Structure of Thermoplastic Polyurethane for Stratospheric Airship Envelope

This study aimed to investigate the effect of artificial weathering test on the photoaging behavior of TPU films. Changes in mechanical properties, morphology and chemical structures are studied by tensile test, scanning electron microscopy, atomic force microscopy, Fourier-transformed infrared, and X-ray photoelectron spectroscopy. The results show that the photoaging negatively affects the initial modulus and stress at break values of TPU films. The surface of the specimen that is exposed to irradiation becomes rough, and some visible micro-defects such as blisters and voids can be detected. The morphology of the fracture surfaces illustrates that irradiation reduces the plasticity but increases the brittleness of the TPU films. The chemical structure analyses of the accelerated aged films prove that chemical structural changes in TPU films occur. The irradiation may break the long molecular chains on the surface of the specimens and form the lowmolecular weight oxygen-containing groups. The number of chain scissions increases with the increase in exposure time.

热塑性聚氨酯(TPU)3D打印研究进展

热塑性聚氨酯(TPU)具有高弹性和生物相容性,在工业和医疗领域中均得到了广泛应用,3D打印技术进一步拓展了TPU材料在医疗领域的应用。但是,热塑性聚氨酯的部分性能特点不利于3D打印成型,在一定程度上限制了其在3D打印中的应用,因此,需要对TPU材料进行改性。从3D打印工艺、工艺参数、专用材料、掺杂改性及先进应用领域研究5个方面,综述了TPU材料3D打印的国内外研究进展。介绍了FDM和SLS 2种可用于TPU材料3D打印的工艺方法,并且对国内外TPU打印材料力学性能与掺杂改性的研究现状进行了总结。同时,分析了TPU材料3D打印在鞋类加工和医学研究领域的应用发展,并且对3D打印TPU在医疗领域的应用前景进行了展望。

Mechanical and Thermal Properties of Sugar Palm Fiber Reinforced Thermoplastic Polyurethane Composites:Effect of Silane Treatment and Fiber Loading

The aim of the present study was to develop sugar palm fiber(SPF)reinforced thermoplastic polyurethane(TPU)composites and to investigate the effects of fiber surface modification by 2%silane treatment and fiber loading(0,10,20,30,40 and 50 wt%)on the mechanical and thermal properties of the obtained composites.Surface treatment was employed to improve the fiber-matrix interface,which was expected to boost the mechanical strength of the composites,in terms of tensile,flexural and impact properties.Thermal properties were also investigated by thermal gravimetric analysis(TGA)and dynamic mechanical analysis(DMA)to assess the thermal stability of the developed composites.Furthermore,scanning electron microscopy(SEM)was used to study the tensile fracture samples of composites with a view towards evaluating the effects of fiber surface treatments on the fiber/matrix interfacial bonding.The findings of this study reveal that the silane treatment has determined good bonding and linkage of the cellulose fiber to the TPU matrix,hence contributing to enhanced mechanical and thermal properties of the composites.The composite formulation with 40 wt%sugar palm fiber loading showed optimum values such as 17.22 MPa for tensile,13.96 MPa for flexural,and 15.47 kJ/m^2 for impact strength.Moreover,the formulations with higher fiber content exhibited satisfactory values of storage modulus and thermal degradation,while their good interfacial adhesion was evidenced by SEM images.

3D打印工艺参数对TPU试样力学性能的影响

热塑性聚氨酯(TPU)作为一种高分子聚合物材料具有高弹性和良好的力学性能,在工业和服装等领域中均得到了广泛应用,3D打印技术进一步拓展了TPU材料在这些领域中的应用。但是3D打印工艺参数对TPU材料成品的力学性能有一定的影响,因此选用直径ϕ1.75 mm的TPU丝材为试验材料,进行了TPU材料FDM打印试样的力学拉伸试验,通过单因素试验方法研究了打印层高、打印温度、填充率、填充方向等打印工艺参数对试样拉伸强度及断裂伸长率的影响规律。研究表明:3D打印工艺参数对TPU试样的力学性能有显著的影响。在打印层高0.2 mm、打印温度220℃、填充率40%、填充方向0°时制备的试样,最大平均抗拉强度为(48.01±1.49)MPa,延伸率为(258±16.52)%,其力学性能优于其他参数制备的试样。通过极差分析得到最大抗拉强度的影响依次为:填充方向>填充率>打印温度>打印层高;对断裂伸长率影响依次为:打印层高>填充角度>打印温度>填充率。

微纳层叠TPU/MVQ热塑性硫化橡胶的制备与性能研究

利用微纳层叠挤出设备良好的分布分散混合作用,制备了聚氨酯/硅橡胶(TPU/MVQ)热塑性硫化橡胶(TPV),研究了制备方法、动态硫化温度、螺杆转速、橡塑比、相容剂种类及含量对TPV性能的影响。结果表明,与普通共混相比,微纳层叠加工制备的TPV在拉伸强度和断裂伸长率上分别提升了12.4%、12.1%;硫化温度190℃、螺杆转速200 r/min时,TPV力学性能最佳,拉伸强度、断裂伸长率、硬度、压缩永久变形分别为6.69 MPa、363.8%、57.6 A、31.5%;随着橡胶含量的增加,TPV拉伸强度、断裂伸长率、硬度下降,弹性回复性能、耐老化性能、耐油性能提升;相容剂硅烷改性聚氨酯(TPSiU)和乙烯丙烯酸甲酯共聚物(EMA)最佳用量分别为10份和5份,与EMA相比,TPSiU作为相容剂时,材料弹性回复性能、耐油性能更优,而EMA对TPV的断裂伸长率提升作用明显。