亲水性聚硅氧烷改性天然乳胶的性能

以亲水性聚硅氧烷KGF-903共混改性天然乳胶,通过拉力试验、老化试验、接触角测量和扫描电子显微镜等研究了聚硅氧烷的添加量对天然乳胶力学性能、抗老化性能、亲水性能和表面形貌的影响。结果表明,KGF-903含量在1.5%时拉伸强度有最佳的改性效果;KGF-903添加量约为3%时断裂伸长率达到最大,老化前后的断裂伸长率比改性前分别提高57%和50%。随着KGF-903含量的增加,改性天然乳胶片的水接触角逐渐减小;扫描电子显微镜观察的结果表明,添加聚硅氧烷能改变乳胶的分散状态。利用小试的最佳配方(即KGF-903的添加量为1.5%)生产了2批次医用导尿管,其表面光洁度、导尿管球囊的成品率、管身硬度、连接器与导尿管排泄锥形接口所承受的拉力和充气漏斗与引流漏斗连接处所承受的拉力等均有显著的提高,有效改善了产品的质量。     

Synthesis and Application of a Novel Organosilane Modifier for Surface Paintability of Organosiloxane Sealants

A novel organosilane, N-n-butyl-γ-aminopropylmethyldimethoxysilane was synthesized through aminization reaction and the chemical structure of resulting products was characterized by ^1HNMR, ^13CNMR, FT-IR and elemental analysis. The results of test on probation for this organosilane proved that it was effective to modify surface-paintability of organosiloxane sealants.     

聚醚改性有机硅表面活性剂的核磁共振及红外光谱表征

通过核磁共振技术(1H,13C NMR,DEPT135,COSY,HSQC,HMBC)和红外光谱技术(FT-IR),对未知的有机硅表面活性剂商品(NPS-A)进行了表征;结果表明:该表面活性剂是单烯丙基聚乙二醇(AllyloxyPolyEthylene Glycol,APEG)在聚硅氧烷侧链改性所得,样品中含有合成时所带的大量DMSO溶剂(合成时所代入的),除溶剂外的主要成分为:(1)M-D20-(D′R)6-M(M:三甲基硅氧基;D:二甲基硅氧基;D′:取代的二甲基硅氧基),其中R=CH2CH2CH2-O-(EO)8-H,平均分子量(M_n)为4 046.0,(2)APEG(M_n=410.0)和(3)聚乙二醇(PolyEthylene Glycol,PEG,M_n=370.0),同时还含有少量由烯丙基衍生而来的小分子成分.     

Bifurcated-tail chiral fluorinated organosiloxane liquid crystalline materials

Abstract

The synthesis and characterization of a series of chiral fluorinated low molar mass (bifurcated tail) organosiloxane materials is presented. The mesogenic moiety is similar to that in the TSiKN65F mesogen reported by Naciri et al., which displays a de Vries-type S_A^* phase. The one parameter varied across the series reported herein is the length of the alkyl chain linking the mesogen moiety to the bifurcated siloxane tail.     

有机硅核-壳型聚丙烯酸酯乳液的合成及油田固砂性能研究

有机硅核-壳型聚丙烯酸酯乳液的合成及油田固砂性能研究;聚丙烯酸酯乳液;有机硅改性;固砂;渗透率     

硅氧烷近晶相单体的合成及应用

为了改善聚合物分散液晶（PDLC）在智能玻璃领域应用中存在的视角较差、透明态效果不够理想以及无法实现双稳态的缺点,合成了一种具有硅氧烷长链结构的近晶相液晶单体,并将该近晶相液晶单体用于近晶相的混晶配方制备了简单的近晶相双稳态器件。以10-溴-1-癸烯、对羟基联苯氰和1,1,1,3,3,5,5-七甲基硅氧烷为原料,以较高收率合成了该近晶相液晶单体。通过核磁共振（NMR）和元素分析（EA）确认了分子结构的正确性;利用偏光显微镜（POM）、示差扫描量热仪（DSC）等对其单体液晶参数和混晶配方参数进行测定,通过基板处理、液晶盒制备、器件老化等过程制备了近晶相双稳态器件。实验表明,该近晶相混晶配方制得的近晶相双稳态器件具有较宽的近晶相温宽（-62℃~60℃）,较低的驱动电压（50 V）,透明态参数优秀（雾度=0.06%,平行光透过率=90.34%）,完全无视角缺陷,且可以仅在状态切换时需要通电实现双稳态效果。该硅氧烷类近晶相液晶单体对于改善近晶相混晶配方有着重要的作用,该材料制备方法简单,原料易得,收率较高,易于生产,对于智能玻璃领域的市场推广有着重要的作用。     

A Redox-Active Microporous Organosiloxane Containing a Stable Neutral Radical,Trioxotriangulene

A new silyl-substituted trioxotriangulene ( TOT ) neutral radical and corresponding porous organosiloxanes (POSs) were synthesized. The neutral radical exhibited a peculiarly high stability and formed a diamagnetic π-dimer characteristic to TOT neutral radicals stabilized by the strong multiple SOMO-SOMO interaction in both solution and solid states. POSs including TOT units within the organosiloxane-wall were prepared by polycondensation of the silyl groups and formed microporous structures with ∼1 nm-size diameters. Redox ability of TOT units in the POS was demonstrated by the treatment of oxidant/reductant in heterogeneous suspension condition, where the TOT units were reversibly converted between reduced and neutral radical species. Furthermore, the solid-state electrochemical measurements of the POS revealed the reversible multi-stage redox ability of TOT units involving polyanionic species within the organosiloxane-wall.     

Oligomeric liquid crystals: From monomers to trimers

A homologous series of linear liquid crystal trimers, the 4,4′-bis[ω-(4-methoxyazobenzene-4′-yloxy)alkoxy]azobenzenes, has been synthesized and characterized. The transitional properties of the trimers are compared with those of the corresponding series of dimers, the α,ω-bis(4-methoxyazobenzene-4′-oxy)alkanes, and monomers, the 4-methoxy-4′-alkoxyazobenzenes. Characteristically pronounced odd-even effects were seen for the transitional properties of both dimers and trimers on varying the spacer lengths. The clearing temperatures of the trimers were higher than those of the corresponding dimers, but as the length of the flexible spacers was increased this difference became rather small. The ratios of T _NI, and ΔS _NI/R for monomer:dimer and dimer:trimer are discussed. These are very similar to reported values for similar materials, suggesting that there may be a rather general relationship between the transitional properties of liquid crystal oligomers as the number of mesogenic units is increased.     

Conformational analysis of siloxane-based enzyme-mimic precursors[1]

The conformational flexibility of six hybrid organodisiloxane oligomers were studied using the Low Mode-Monte Carlo conformational search method with the MM2* force field and the Generalized Born/Surface Area continuum solvent model for water. These systems have enzyme-like properties as synthetic acyltransferases and contain aminopyridine groups in various states of protonation. An ensemble of low energy structures was generated and used to investigate the dependence of molecular shape and flexibility on protonation, which plays an important role in catalyst solubility and self-association. The results as measured by the number of unique conformations, end-to-end or longest intramolecular distance and radius of gyration of the conformational point cloud indicate that the number of protonated pyridines plays a significant role in the overall molecular shape. A similar study was also carried out on various POSS-substitutive organodisiloxane oligomers.