多面体低聚倍半硅氧烷对环氧树脂热性能影响分析

选用有机-无机纳米杂化材料乙烯环氧基多面体低聚倍半硅氧烷(EOVS)和环氧醚基多面体低聚倍半硅氧烷(GPOSS)为改性剂,与4,4′-二氨基二苯甲烷环氧树脂共混制得不同改性剂质量分数(树脂与改性剂总质量的百分数)的EOVS或GPOSS改性环氧树脂,考察了改性树脂的固化反应程度、玻璃化转变温度(Tg)和热稳定性.结果表明...     

氰酸酯树脂/八(γ-氯丙基)多面体低聚倍半硅氧烷复合材料

采用八(γ-氯丙基)多面体低聚倍半硅氧烷(T8)改性氰酸酯树脂(CE)制备了系列CE/T8复合材料。研究了复合材料的冲击性能、动态热力学性能、热稳定性能以及断面形貌。结果表明:T8的加入能明显提高复合材料的冲击性能,当加入10%的T8时,复合材料的冲击强度较纯CE提高了12.29 kJ/m2;复合材料在高温阶段(大于500℃)的热稳定性与纯CE相比有一定提高,有助于改善CE的阻燃性能;T8的加入使复合材料的玻璃化转变温度和储能模量均有所降低。     

八叠氮基聚倍半硅氧烷的合成及表征

以对羟基苯甲酸、八（二甲基硅氧基）聚倍半硅氧烷、叠氮化钠为原料,经酯化、醚化、水解、硅氢加成等反应制备了八叠氮基的六面体聚倍半硅氧烷[POSS-（N3）8],通过1H NMR、13C NMR、FT-IR对其进行了表征;并探讨了叠氮化反应温度对POSS-（N3）8产率的影响。结果表明,随着叠氮化反应温度的降低,POSS-（N3）8的产率逐渐增加;当叠氮化反应温度为70℃时,POSS-（N3）8的产率达到60%。     

多面体低聚倍半硅氧烷改性PU的制备

采用多面体低聚倍半硅氧烷(POSS)对聚氨酯(PU)进行改性,并对改性PU的性能进行研究。结果表明:采用超声波分散法可将POSS均匀分散在PU基体中;八乙烯基POSS对PU具有较好的补强和增韧作用,而八苯基POSS对PU的补强作用不明显。     

苯胺甲基笼型倍半硅氧烷改性环氧树脂的性能

研究了苯胺甲基笼型倍半硅氧烷(PAM-POSS)/环氧树脂(E-44)/MeTHPA/TEA体系的固化反应及其热性能,并考察了固化杂化树脂的力学性能。结果表明:随着PAM-POSS含量的增加,杂化树脂的冲击强度和弯曲强度呈先增大后下降的趋势,当PAM-POSS质量分数为10%时,冲击强度和弯曲强度达到最大值。     

多面体低聚倍半硅氧烷的最新研究进展

综述了多面体低聚倍半硅氧烷(POSS)的研究进展,主要介绍了它的常见结构、特性、合成方法和应用,展望了POSS合成研究的发展趋势。     

Synthesis,Morphology, and Viscoelastic Properties of Polyhedral Oligomeric Silsesquioxane Nanocomposites with Epoxy and Cyanate Ester Matrices

Octaaminophenyl(T₈)POSS [1, (C₆H₄NH₂)₈(SiO_1.5)₈] and dodecaaminophenyl(T₁₂)POSS [2, (C₆H₄NH₂)₁₂(SiO_1.5)₁₂] were synthesized, characterized and then incorporated into two types of thermoset resins: (1) the bisphenol-F-based cyanate ester resin, PT-15, and (2) epoxy (Epon 828, Shell Chemical Corp.)/4,4′-diaminodiphenylmethane (DDM) resin, respectively, to make two series of nanocomposites. The sum of amino groups in both DDM and POSS were held in a 1:1 mole ratio to the epoxy groups. EPON-828/1/DDM and EPON-828/2/DDM composites (78.63/0/21.37, 77.48/5/17.52, 76.34/10/13.66, 74.05/20/5.95 and 72.28/27.72/0 wt/wt/wt compositions for both series) were prepared. PT-15/1 and PT-15/2 composites (99/1, 97/3 and 95/5 wt/wt compositions for both types) were also prepared. These nanocomposites were characterized by transmission electron microscopy (TEM), dynamic mechanical analysis (DMA), solvent extraction and FT-IR. In all systems, POSS 1 and 2 were chemically bound into the resin matrix and phase-separated POSS particle domains were not observed. Incorporation of both 1 and 2 can dramatically elevate the high temperature bending storage moduli, E′, of epoxy resins.     

笼形氨丙基聚倍半硅氧烷/聚乳酸杂化材料的制备与性能

用溶液共混的方法,制备了不同质量分数的笼形氨丙基聚倍半硅氧烷(OAPS)与聚乳酸(PLLA)杂化材料。用傅立叶红外光谱(FTIR)、差示扫描量热法(DSC)、动态热机械分析(DMA)、热失重分析(TGA)等手段对该体系进行了考察。结果表明,OAPS质量分数为5时,PLLA的羰基伸缩振动峰由1758cm-1红移至1748cm-1,OAPS氨基伸缩振动峰由3362cm-1红移至3296cm-1,说明PLLA羰基与OAPS氨基之间形成了氢键;随着OAPS质量分数由0增至5,OAPS/PLLA杂化材料的玻璃化转变温度(Tg)由47℃升高至56℃,熔融温度(Tm)由141℃升高至146℃,储能模量由1100MPa增至1250MPa;OAPS的加入没有改变PLLA的热分解温度。     

硅系阻燃剂研究进展

综述了近年来有关硅系阻燃剂的结构与性能以及阻燃改性等方面的研究进展。介绍了无机硅系阻燃剂 (包括聚合物/层状硅酸盐以及聚合物/二氧化硅纳米复合材料)的热稳定性和阻燃性能。侧重论述了有机硅系阻燃剂(包括本质阻燃聚合物、笼状倍半硅氧烷及其改性聚合物)的热稳定性、阻燃性能和阻燃机理。     

八氨基倍半硅氧烷改性聚酰胺酰亚胺基润滑涂层的性能研究

为开发苛刻服役环境下高性能、长寿命的有机润滑涂层,以氨基丙基三乙氧基硅烷（KH550）为原料制备了八氨基倍半硅氧烷（ NH₂-POSS）,并将其添加到聚酰胺酰亚胺基涂层（ HM-1100A）中,研究了改性前后涂层的结构、力学性能和摩擦性能。结果表明：经 NH2-POSS改性后的 HM-1100A涂层相比原始涂层具有更高的硬度、内聚强度及较低的表面能,并且涂层的摩擦性能有显著提高。通过对比 HM-1100A、KH550改性 HM-1100A及 NH₂-POSS改性 HM-1100A 3种涂层的热重、硬度、表面能和摩擦性能,研究了其作用机理,分析发现 NH₂-POSS独特的中空笼形结构和八官能团的引入有效提高了涂层的物理机械性能和摩擦性能。     

三聚氰胺基阻燃剂在环氧树脂中的应用进展

介绍了环氧树脂的燃烧机理和三聚氰胺基阻燃材料的阻燃机理。综述了三聚氰胺基阻燃材料在环氧树脂塑料中的应用现状和阻燃效果。同时对三聚氰胺基阻燃材料的发展趋势及应用前景进行了分析和展望。。     

Thermal Properties of Organic-inorganic Hybrid Composites Based on Multi-Epoxy Silsesquioxane and Epoxy Resin

The multi-epoxy cubic silsesquioxane (SSQE) was successfully introduced into epoxy resin (EP) and formed the organic-inorganic EP-SSQE hybrids. The hybrids were cured by 4,4′-diaminodiphenylsulphone (DDS) and the Fourier transformation infrared (FTIR) spectra were used to monitor the cured reaction of the hybrid, and the results showed that the hybrids could be cured thoughtfully without influence the cubic silsesquioane structure. The thermal properties of the hybrid such as the heat distortion temperature (HDT), the glass transition temperature Tg and the thermal decomposing property were studied. The results showed that the hybrids had the higher thermal properties than that of the pure epoxy resin for the introducing of multi-epoxy cubic silsesquioxane.     

UV Curing of Organic‐Inorganic Hybrid Coatings Containing Polyhedral Oligomeric Silsesquioxane Blocks

Hybrid nanocomposite coatings were prepared by the UV‐curing technique with a methacrylic oligomer and multifunctional methacrylic polyhedral oligomeric silsesquioxane blocks (POSS®). The results obtained from the polyhedral compounds were compared with those of a disordered framework obtained by the condensation of a silica precursor (MEMO). The inorganic domains generated during synthesis created constraints in movement of polymer segments, which reflected in an increase in T_g of the hybrid nanocomposite coatings. The films were transparent. The random structure obtained by the condensation of the MEMO showed a stronger effect on T_g than that observed by introducing POSS®. The effect of inorganic domains reflected on thermal stability, surface hardness and mechanical properties of the hybrid nano‐composite coatings.

     

乙烯基聚硅氧烷包覆改性聚磷酸铵及其在环氧树脂中的阻燃应用

以正硅酸乙酯（ＴＥＯＳ）与乙烯基三乙氧基硅烷（ＶＴＯＳ）为前驱物,采用溶胶凝胶工艺将乙烯基引入聚磷酸铵（ＡＰＰ）的表面,以期对ＡＰＰ进行二次接枝改性。对ＶＴＯＳ改性ＡＰＰ（ＶＭＡＰＰ）进行了研究,并研究了其对环氧树脂（ＥＰ）阻燃性能的影响。结果表明,包覆膜材料中存在乙烯基;经含有乙烯基的聚硅氧烷对ＡＰＰ进行包覆改性后,在ＡＰＰ表面生成一层致密的保护膜,表面Ｐ、Ｎ 元素含量明显降低,Ｃ元素含量明显增加,出现Ｓｉ元素的吸收峰;ＶＭＡＰＰ的疏水性及耐水性均得到改善;ＶＭＡＰＰ能够促使ＥＰ生成更为致密和稳定的炭层,促进ＥＰ阻燃性能的改善。     

用于环氧树脂磷-氮阻燃固化剂的合成及应用

以1,2-环己二胺(DACH)和苯基膦酰二氯(PPDC)为原料合成了一种新型环氧树脂(EP)阻燃固化剂苯基膦酰-1,2-环己二胺(PPDAC),并用傅里叶变换红外光谱(FTIR)、氢核磁共振(¹HNMR)和热重分析仪(TGA)对其进行了表征,制备了系列PPDAC/EP,采用TGA、极限氧指数(LOI)、垂直燃烧试验和扫描电镜(SEM)研究了其热稳定性、阻燃性和炭层形貌。结果表明:PPDAC的填充可以提高EP树脂的阻燃性能,添加PPDAC的EP残炭率和阻燃性均得到提高,但其初始分解温度和力学性能下降。添加PPDAC的EP残炭表面发泡膨胀明显,阻燃效果优异。     

Hybrid Organic-Inorganic Nanocomposites Based on Poly(ϵ-Caprolactone)/Polyhedral Oligomeric Silsesquioxane: Synthesis and In Vitro Evaluations

Hybrid poly(?-caprolactone) (PCL) containing nanocomposites and non-hybrid linear PCL diols were synthesized by anionic ring opening polymerization of ?-caprolactone on a POSS or ethylene glycol central blocks, respectively. Monolith scaffolds were then fabricated from the hybrid nanocomposites and non-hybrid linear PCL diols via non-solvent induced phase separation technique. The effects of inclusion of POSS nanocage in the polymer chain structure on specific surface area and pore size of the scaffolds was investigated by multipoint BET method. This perfect scrutiny will introduce an excellent nanoparticle pendent to the PCL chains to promote the in vitro properties of the implants potentially applicable in tissue engineering.     

气相二氧化硅对环氧树脂的辅助阻燃作用

将气相Si O2与含膦阻燃剂复配,应用到环氧树脂(EP)中,着重研究了该复合材料的阻燃性能、热分解性能及玻璃化转变温度(Tg),结果表明当气相Si O2含量为3%时,复合材料的氧指数值达到28.3%,垂直燃烧通过UL94 V-0标准。在热分解过程中,各组分之间相互作用,复合材料的玻璃化转变温度比纯EP的要高,残炭率也增加。可见气相Si O2起到一定的辅助阻燃作用。     

DOPO型环氧树脂用阻燃剂的合成与应用研究

以对苯二胺、4-氟苯甲醛、4-硝基苯甲醛、4-甲氧基苯甲醛、9,10-二氢-9-氧-10-磷杂菲-10-氧化物(DOPO)为原料,经两步反应,合成了3种含磷、氮的DOPO型环氧树脂用阻燃剂,通过1HNMR、FTIR对中间体及目标产物结构进行了表征。将合成的阻燃剂按0.00%、5.00%、10.00%、15.00%、20.00%(按环氧树脂质量计算)加入到环氧树脂(EP)中,加入4,4'-二氨基二苯基甲烷(DDM)固化后得到透明的复合材料,并对复合材料的热稳定性和阻燃性能进行了初步评价。结果表明,添加阻燃剂后的固化物初始失重温度高于300℃,可满足高分子材料加工时对热稳定性的要求;随着固化物中磷含量的增加,固化物的阻燃性增大;当固化物中磷质量分数达到1.00%时,所有固化物都可以达到UL94 V-0级,测得其中N,N'-双[1-(4-硝基苯基)-1-(9-氢-9-氧杂-10-磷杂菲-10-氧化物)-甲基]-1,4-苯二胺(BNP-DOPO/DDM/EP)固化物的极限氧指数(LOI)值为37.0,是三组固化物中最高者。     

碱在合成溴化环氧树脂阻燃剂中的关键作用

研究了碱在四溴双酚A和环氧氯丙烷(相转移催化条件下)缩聚生成高分子量溴化环氧树脂阻燃剂过程中的作用。结果显示:合成溴化环氧树脂过程中,分别选用四乙基溴化铵、四甲基溴化铵、聚乙二醇(分子量6,000和分子量400)等相转移催化体系,LiOH、NaOH、KOH等对环氧树脂产品(分子量、收率和Br含量)产生显著影响并且影响程度差异较大,LiOH效果最好,KOH次之,NaOH最差。碱用量以保证得到预期产品的前提下最低用量为宜。