有机硅改性水性聚氨酯-丙烯酸酯乳液的制备及性能

采用种子乳液聚合方法合成了具有核壳结构的有机硅改性水性聚氨酯-丙烯酸酯复合乳液,TEM测试结果表明,该乳液具有核壳结构。通过共混与共聚体系衰减全反射红外光谱(ATR-FTIR)的比较及表面光电子能谱(ESCA)研究证实有机硅链段已被化学键入聚氨酯-丙烯酸酯分子链中,且硅氧烷链段有表面富集的倾向。表面水接触角及耐水性测试结果表明,随着有机硅含量的增加胶膜的水接触角增大,耐水性提高。     

密集侧链有机硅改性水性聚氨酯分散体的合成与胶膜表面性能

首先采用单端双羟基聚硅氧烷与二异氰酸酯反应合成了硅氧烷密集侧链片段，而后与二异氰酸酯、聚醚（聚酯）二元醇、二羟甲基丙酸、小分子扩链剂合成有机硅侧链密集集中于聚氨酯链段中某些区域的改性水性聚氨酯分散体。采用GPC追溯了反应过程，采用接触角测定仪、XPS、SEM表征了胶膜表面特性；采用接触角测定仪研究了胶膜在水中浸泡72 h后表面疏水性变化。结果表明：密集侧链改性水性聚氨酯胶膜表面有机硅富集程度远高于对应的随机侧链改性水性聚氨酯，同时密集改性水性聚氨酯胶膜在水中浸泡72 h后，胶膜表面疏水性保持且略有提高。     

有机硅共聚改性水性聚氨酯PU—SI的制备及性能研究

以聚醚（聚酯）多元醇、有机硅低聚物（PDMS）、多异氰酸酯、扩链剂和亲水扩链剂为主要原料，制备有机硅共聚改性聚氨酯乳液PU－SI。利用现代分析测试手段红外光谱（FT－IR）、核磁共振图谱（NMR）、凝胶色谱（GPC）、电子能谱（ESCA）、接触角仪、电子拉力试验机等，对合成产物的化学结构及性能进行表征和分析研究。结果表明：有机硅改性PU乳液稳定性好，硅氧烷链段可在乳液胶膜表面富集，对PU材料有明显的表面改性作用，使其耐水性提高，而本体力学性能变化不大，作为顶层涂料，有很好的综合性能。     

聚乙二醇对混合嵌段聚氨酯透湿性能的影响

综合考虑聚酯型聚氨酯和聚醚型聚氨酯的特点,以聚己二酸丁二醇酯(PBAG)和聚乙二醇(PEG)混合作为软段,采用溶液预聚法制备了聚酯-聚醚混合型聚氨酯。考察了混合软段中PEG摩尔分数以及PEG相对分子质量对聚氨酯薄膜的表面接触角、吸水率、透湿率及力学性能的影响。结果表明,随着PEG摩尔分数的增大和PEG相对分子质量的增大,薄膜的接触角和拉伸强度降低,吸水率、透湿率增大。当PEG摩尔分数从0.28增加到0.71时,薄膜接触角从75.8°降低至63.5°,吸水率从25.7%增加到106.1%,透湿率从1226g/(m2·24h)增加到3408g/(m2·24h);PEG相对分子质量从1000增加到10000时,薄膜接触角从80.5°降到55.7°,吸水率从4.5%增加到356.4%,透湿率从733g/(m2·24h)增加到3577g/(m2.24h)。     

软段对水性聚氨酯木器涂料性能的影响

合成了系列水性聚氨酯乳液,研究了低聚物多元醇种类及分子量不同对水性聚氨酯涂料性能的影响。结果表明:聚酯型水性聚氨酯随着软段分子量的增大结晶程度增加,机械强度和硬度较聚醚型高,耐水性较好;结构规整,易结晶的软段合成出的聚氨酯树脂力学性能和耐水性能都较好;而有机硅氧烷改性可以提高聚氨酯材料的耐水性。     

具有规整硬段结构的水性聚氨酯的制备及物理性能

从分子设计的角度出发,以二苯甲烷-4,4’-二异氰酸酯、二羟甲基丙酸、1,4-丁二醇、异佛尔酮二异氰酸酯、乙二胺和聚酯多元醇为原料,采用分步法制备了具有不同硬段结构、室温贮存稳定的聚氨酯水分散液。结果表明,随着硬段质量分数的增加,聚氨酯水分散液的粒径减小,但粒径分布不变。在聚氨酯水分散液成膜后的表面上,水的接触角增大,膜的吸水率显著降低。硬段质量分数为50％的聚氨酯水分散液成膜后表现出优异的耐水性能。     

水性聚氨酯-有机硅共聚物的制备与性能

以聚醚二元醇(GE2000)为软段,环氧树脂(E-20)为部分硬段,制备出有机硅交联改性的聚氨酯乳液,探讨了有机硅含量对乳液性能的影响。结果表明,随着有机硅含量增大,乳液黏度、分子量增大,胶膜耐水(溶剂)性、机械性能、疏水性增强。FTIR分析证实有机硅键合到聚氨酯结构中。SEM分析表明,有机硅改性聚氨酯胶膜结构致密。DSC与DMA分析表明,有机硅改性聚氨酯软硬段之间存在一定程度的微相分离,有机硅含量的增加提高了其耐热性能。     

一种用于聚醚多元醇的抗氧剂

<正>聚氨酯的稳定取决于其分子结构,尤其是其中的多元醇的结构。一般情况下,含有聚酯链段的聚氨酯稳定性要远优于含聚醚链段的聚氨酯,应用于聚氨酯软泡海绵的聚醚多元醇由于在后续发泡过程中内部温度偏高,其抗氧剂体系一直是研究的重点。聚氨酯的稳定涉及聚氨酯生产厂家和多元醇生产厂家。随着近年来聚氨酯,尤其是聚氨酯软泡海绵应用领域的新要求,直接对聚氨酯软泡海     

水分散有机硅-聚氨酯嵌段共聚物的制备与性能研究

以端羟基聚二甲基硅氧烷（PDMS）和氨烃基硅烷偶联剂（DB-912）为原料,合成了端氨烃基聚二甲基硅氧烷低聚物（NS）,并以此作为扩链剂,制备了水分散有机硅-聚氨酯嵌段共聚物（WPSUR）。考察了NS的摩尔质量与扩链剂类型对乳胶粒粒径、薄膜疏水性与耐热稳定性的影响。结果发现,随着NS摩尔质量的增加,乳液粒径增大;扩链剂类型对乳液及薄膜性能影响较大,采用NS为扩链剂制备的WPSUR,乳液呈现较高的表现黏度,薄膜吸水率较低、对水的表面接触角达103&#176;,疏水性较好;与引入小分子硅烷偶联剂的体系相比,体系中有机硅链段含量大大增加,耐热稳定性良好;水分散液均呈现良好的离心稳定性,乳液具有良好的耐高温性能与冰冻-解冻稳定性。     

有机硅聚醚嵌段聚氨酯乳液的研究

合成了稳定的有机硅聚醚嵌段聚氨酯乳液，通过透射电镜、旋转粒度分布仪、电子拉力机和动态力学性能测试等方法研究了有机硅链段的含量和链长对乳液及其膜性能的影响。结果表明，有机硅链段含量增加。PSU复合乳液稳定性下降，乳液粒径分布由单分散变成多分散。此外，有机硅链段分子质量对PSU膜的微相结构有重要影响，增加PSiO软段有利于体系硬段的微相分离，短的PSiO链与长的聚醚链相容性更好。     

Synthesis, Characterization and Surface Properties of Cross-linked Polyurethane Dispersions Modified by Organosiloxane

A series of cross-linked polyether-polyester polyurethane dispersions modified with organosiloxane were prepared based on hydroxyl-terminated polydimethylsiloxane (HTPS) as hydrophobic component and 3-aminopropyl-triethoxysilane (APTS) as cross-linker as well as a bridge between polyurethane (PU) and polysiloxane (PSIL). It was discovered that polydimethylsiloxane segments were incorporated into PU chains chemically and organosiloxane was preferentially oriented toward the surface layer of the film by making a comparison of attenuated total reflection (ATR) spectra between the copolymer and the blend of PU and PSIL, which was further confirmed by investigation of electron spectroscopy for chemical analysis (ESCA). The relationships between surface properties of the film formed from polyurethane dispersion and organosiloxane content were also studied. The results showed that water contact angle of the film increased with the increase of organosiloxane content. Interestingly, it was also found that water contact angle of PUS film increased firstly and then decreased when film-forming temperature varied from 25℃ to 55℃.     

基于EPDMS的水性聚氨酯合成与表面性能研究

首先采用酸催化平衡反应合成一种双氢封端的聚硅氧烷低聚物(HPDMS),然后通过HPDMS与单烯丙基封端的聚醚的硅氢化反应合成了一种聚醚嵌段聚硅氧烷二元醇,单丙基聚醚-b-聚二甲基硅氧烷-b-单丙基聚醚(EPDMS)。通过IR、NMR等分析手段对其结构和组成进行了鉴定和表征。以不同分子量EPDMS为软段,制备出一系列硅改性水性聚氨酯(P-PUD),对P-PUD接触角的研究发现,聚合物膜表面接触角随着温度的上升而增加,表明硅氧烷在聚氨酯表面的富集不充分,其原因主要是聚合物分子间相互作用与硅氧烷向聚合物表面的富集是一个竞争过程。     

聚酯型聚氨酯膜的溶胀性能及膜分离性能研究

研究通过两步法反应,制备了一系列聚酯型聚氨酯（包括环糊精嵌段）,并采用红外,热分析等手段对其结构与性能进行了表征,并且考察了链段中的环糊精对膜溶胀性能的影响以及膜对不同混合物体系的分离性能。结果表明,链段中含环糊精的膜在有机混合物中有较大的溶胀度,聚酯型聚氨酯对于苯-环己烷和水-乙醇体系均有较好的分离性能。     

Study on polyethylene glycol/polydimethylsiloxane mixing soft‐segment waterborne polyurethane from different mixing processes

The surface structure and physical properties of polyethylene glycol series polyurethane (PEG‐PU) membranes, in which were introduced hydrophobic polydimethylsiloxane (PDMS) component by the procedure of PU blending or of soft‐segment copolymerization, were studied in this investigation. In the case of the blending process, the synthesized waterborne polyurethanes (WBPUs) of PEG–PU and of polydimethylsiloxane series polyurethane (PDMS–PU) were combined, whereas in the copolymerization process PEG and PDMS were taken as mixed soft segments to polymerize the WBPU. For the blending method, glass‐transition and melting temperatures increased rapidly when a small amount of PDMS–PU was added to PEG–PU and reached a maximum with 5% PDMS–PU mixed in. However, in the case of the copolymer method, thermal properties closely followed predicted values. From dynamic mechanical analysis studies it was found that a low PDMS–PU content ratio could increase the rubbery elasticity of PEG–PU membrane and improve its strength simultaneously in the blending method, and the copolymer method only caused PU to gain some natural complementary strength and elasticity. Electron spectroscopy for chemical analysis studies indicated that PDMS migrated to the surface much more easily in the blending method than in the copolymer method. The SEM studies also found that, in the blending method, the numbers of pores were less than those in the copolymer method. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 233–243, 2003     

PU／SBA-15介孔分子筛复合材料的制备及性能研究

采用预聚法制备聚氨酯（PU）／SBA-15介孔分子筛复合材料，并采用DSC、SEM、DMA和TG等方法对复合材料进行表征。结果表明，PU／SBA-15分子筛复合材料与纯聚氨酯相比，拉伸强度有所提高，耐撕裂性能明显增大；复合材料的耐热性能和耐溶剂性能提高不明显；SBA-15分子筛对聚氨酯软硬段的微相分离影响较小。     

Mechanical and surface properties of membranes prepared from waterborne cationic hydroxyl‐terminated polydimethylsiloxane/polyurethane surfactant‐free micro‐emulsion

With the action of catalyst and cosolvent, a series of hydroxyl‐terminated polydimethylsiloxane (HPMS) based polyurethane (PU) micro‐emulsion were gotten by surfactant‐free copolymerization. They were successfully prepared by reacting isophorone isocyanate, poly(tetramethylene glycol), and HPMS with N‐methyldiethanolamine (MDEA) as chain extender and trimethylolpropane (TMP) as crosslinker. After neutralizing with dimethyl sulfate and inversing the emulsion polymerization with deionized water, a series of microemulsions were obtained. The emulsions were then cast into membranes named as PU–HPMS. The mechanical properties and water absorption of the PU–HPMS were determined and simultaneously the effects of the content of hard segment, solvent, TMP, MDEA, HPMS, and the molecular weight of soft segment were studied. It is noticed that the tensile strength decreased and elongation at break increased in the HPMS/PU when compared with pure PU, which confirm that PU was end‐capped with PDMS. It is also noticed that water absorption increased in the HPMS/PU when compared with pure PU. As HPMS content increased from 0.0 to 25.0 wt %, the surface free energies decreased from 0.3446 to 0.2317 mN/cm and water absorption decreased from 11.2% to 0.14%. The surface free energies of the membranes were decreased by more than 32.76%, which demonstrate that the membrane surfaces have excellent water and oil repellency. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 40–46, 2006     

聚氨酯/层状双金属氢氧化物复合膜的制备和性能研究

利用静电纺丝设备制备了层状双金属氢氧化物(LDH)增强的聚氨酯(PU)电纺复合膜(复合膜),采用扫描电子显微镜(SEM)、广角X射线衍射(WAXD)、电子万能试验机、差热式扫描分析仪(DSC)和热重分析仪(TG)对PU/LDH复合膜的形貌、力学性能以及热稳定性进行了分析。研究结果表明,添加少量的LDH就能使复合膜强度有明显提高,当LDH含量为1%(质量分数)时复合膜的强度提高到16.2 MPa左右,相对电纺制备的纯PU膜,提高幅度约为217%;而PU/LDH复合膜的断裂伸长率保持了较高的水平,达到了约165%。扫描电镜(SEM)显示,加入LDH有利于电纺,所得纤维的直径有小幅度下降。WAXD分析结果表明,LDH在PU中并未形成插层结构,LDH与PU的混合类似于传统共混过程。DSC分析结果表明,LDH对PU软段的玻璃化转变温度无显著影响,但是对PU硬段的结晶有一定的促进作用。TG分析结果表明,复合电纺膜的起始分解温度相对PU电纺膜有一定程度的降低。     

Silicon‐containing anionic water‐borne polyurethane with covalently bonded reactive dye

A silicon‐containing water‐borne polyurethane (PU) polymer with hydroxyl side groups was synthesized that was stable in basic conditions and also capable of reacting with a reactive dye to form a covalently bonded dye molecule. The silicon‐containing anionic water‐borne PU prepolymer was synthesized from H₁₂‐4,4′‐diphenylmethane diisocyanate (H₁₂‐MDI), polytetramethylene glycol, polydimethylsiloxane (PDMS), 2,2′‐bis(hydroxymethyl), propionic acid (anionic centers), and triethyleneamine using the prepolymer mixing method. Water was then added to emulsify and disperse the resin to form an anionic water‐borne PU prepolymer. N‐(2‐Hydroxyethyl ethylene diamine) (HEDA) was used to extend the prepolymer to form a water‐borne PU polymer with a side chain of hydroxyl groups, which can further react with the reactive dye to form a dyed PU. The reactive dye of chlorosulfuric acid esters of sulfatoethyl sulfones can react with the water‐borne PU polymer. Behaviors of alkali resistance and dyeing properties were observed. In consideration of thermal properties, the dye‐grafted PU polymers exhibited lower glass‐transition temperatures for soft segments and hard segments than those without dye. Concerning mechanical properties, it was found that the modulus and the strength of the dyed PU polymers decreased with grafting of the dye molecule, but elongation at break was increased. The alkali resistance increased with PDMS content. For dye‐uptake properties, the percentage of dye grafting was over 90%. Also, the dye‐grafted PU exhibited a lower percentage of dye migration than that of polymers with ethylene diamine instead of HEDA as a chain extender, and showed greater colorfastness to light. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2045–2052, 2003     

Synthesis and characterization of hydroxypropyl terminated polydimethylsiloxane‐polyurethane copolymers

Polyurethane (PU) block copolymers were synthesized using prepared hydroxypropyl terminated polydimethylsiloxane (HTPDMS MW 990) and polyether diols (N‐210) as soft segment with 4,4′‐diphenylmethane diisocyanate (MDI) and 1,4‐butanediol. This low molecular weight polydimethylsiloxanes (PDMS) containing hydroxypropyl end‐groups displayed better compatibility with PU than common PDMS. In this article, we illustrate its synthesis routes and confirmed the proposed molecular structures using NMR and infrared radiation (IR). We varied the contents of HTPDMS and N‐210 in soft segments (HTPDMS—N‐210: 0 : 100, 20 : 80, 40 : 60, 60 : 40, 80 : 20, and 100 : 0) to synthesize a series of PDMS‐PU copolymer. IR spectroscopy showed the assignment characteristic groups of each peak in copolymers and confirmed that the desired HTPDMS‐PU copolymers have been prepared. The different thermal, dynamic mechanical and surface properties of the copolymers were compared by thermogravimetry, DMA, contact angle and solvent resistance. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013