聚多巴胺修饰固体材料表面研究进展

从多巴胺单体特性、多巴胺自聚与黏附机理、直接改性方法及相关基体(有机材料、无机材料)的功能化改性等方面对近年来聚多巴胺修饰的相关实验研究进展进行了综述,并综述了聚多巴胺涂层的进一步功能化的研究进展。     

纳米SiO2表面修饰及在聚乳酸中的应用

为了降低纳米SiO2的表面能,防止团聚,提高分散性,应用硅烷偶联剂KH-550对纳米SiO2进行表面修饰.分析KH-550用量、反应时间对纳米SiO2修饰效果的影响关系,并应用SEM对纳米SiO2修饰前后形貌进行观测,应用SEM、DSC对聚乳酸/纳米SiO2复合材料进行表征.结果得出纳米SiO2最佳修饰工艺为:KH-550用量5％,反应时间2h.最优工艺修饰的纳米SiO2结构松散,在聚乳酸中分散均匀,复合体系的玻璃化转变温度提高了4.29℃,玻璃化转变温度处的热焓提高了2.431 J/g.     

直接从水玻璃合成表面修饰的纳米SiO2微粒

采用溶胶-凝胶法，以水玻璃为原料，在加入复合表面活性剂和分数剂的条件下，与乙酸反应直接得到纳米表面修饰的SiO2微粒。TEM照片显示，纳米SiO2颗粒为球形，粒度为10-30nm，统计平均粒径为20nm。     

聚甲基丙烯酸甲酯/SiO2纳米复合物的制备

基于纳米SiO2表面羟基与γ-甲基丙烯酰氧基丙基三甲氧基硅烷间的缩合反应,于SiO2表面引入双键.以甲基丙烯酸甲酯为单体,偶氮二异丁腈为引发剂,采用原位自由基聚合的方法,制备了聚甲基丙烯酸甲酯/SiO2纳米复合材料.FTIR和TGA证实聚甲基丙烯酸甲酯大分子链成功接枝在SiO2表面.聚合体系黏度是影响SiO2表面聚甲基丙烯酸甲酯接枝率的关键因素.甲基丙烯酸甲酯浓度为6 mol/L,偶氮二异丁腈浓度为0.05～0.1 mmol/L时,SiO2表面聚甲基丙烯酸甲酯接枝率可达到94％;SiO2用量对表面接枝聚合没有影响.     

聚合物/纳米SiO2复合材料的研究进展

介绍纳米SiO2的特性、表面改性及分散技术,以及聚合物/纳米SiO2复合材料的制备方法。对近年来聚合物/纳米SiO2复合材料的研究进展情况进行了综述。指出聚合物/纳米SiO2复合材料具有广阔的应用前景,但尚存在许多需进一步深入研究的问题。     

丙烯酸酯类聚合物乳液法修饰纳米SiO2粒子研究

采用带有羧基活性官能团的丙烯酸酯类聚合物乳液对纳米SiO2进行表面修饰.并用透射电镜、红外、热失重、接触角、粒径分析对处理效果进行了表征.结果表明所制备的含羧基基团的共聚物乳胶粒子在机械搅拌作用下,与粒径为15～20nm左右的无机SiO2纳米粒子的作用过程中,实现了对SiO2表面修饰和分散的效果.当复合温度(65℃)高于改性用聚合物的Tg(45℃)时,柔软的聚合物乳胶粒子变形、黏附在SiO2纳米粒子周围,并通过羧基的化学吸附作用最终实现对SiO2粒子的包覆;当复合温度(25℃)低于改性用聚合物的Tg(45℃)时,乳胶粒子仍保持其基本形状,SiO2粒子黏附在乳胶粒子周围.     

SiO2纳米颗粒对水相泡沫稳定性的影响

采用SiO_2纳米颗粒分别与阴离子表面活性剂十二烷基硫酸钠（SDS）、阳离子表面活性剂十六烷基三甲基溴化铵（CTAB）、非离子表面活性剂十二烷基醇聚氧乙烯（3）醚（AEO-3）复配制备水相泡沫,研究了发泡体积、半衰期和微观结构的变化规律,以揭示SiO_2纳米颗粒对水相泡沫稳定性的影响机理。结果表明,在表面活性剂质量分数一定的条件下,随着纳米颗粒质量分数的增加,泡沫稳定性逐渐增强,当纳米颗粒质量分数为0.3%时,发泡体积达最大值,含气率分别为78.9%,78.4%和78.8%。与单组分质量分数分别为0.3%,0.3%和15%的SDS、CTAB、AEO-3体系相比,发泡体积未受影响,半衰期分别为9.0,8.2和360?min,提高了20%,28.1%和71.4%,泡沫的稳定性得到了不同程度的改善。     

使用环境对SiO2纳米颗粒表面亲油性的影响

利用Washburn法对SiO_2纳米颗粒的表面亲油性进行了测定,系统地研究了使用环境对其亲油性的影响规律。结果表明:当pH值、温度、盐浓度、盐种类以及使用时间变化时,疏水型SiO_2纳米颗粒的表面亲油性明显增强。其中,在pH=13、温度为20℃、使用时间为2 h时,增强最明显。此外,盐度较大时,有利于提高SiO_2纳米颗粒的表面亲油性。最后,亲水型SiO_2纳米颗粒表面亲油性的变化趋势与上述类似。盐浓度、使用时间等变化时,其表面亲油性也有所增强。     

表面活性剂对镀镍液中SiO2纳米颗粒分散的影响

电镀溶液中纳米颗粒的分散是复合镀技术中需要解决的首要问题,以十六烷基三甲基溴化铵和聚乙二醇-10000为分散剂,对镀镍溶液中的SiO2纳米颗粒进行改性.通过沉降实验对表面改性后的SiO2纳米颗粒悬浮液的稳定性进行了比较分析.结果表明,当十六烷基三甲基溴化铵和聚乙二醇-10000在悬浮液中的质量浓度分别为2g/L和1.5g/L时,SiO2纳米颗粒能够均匀悬浮,稳定分散.     

多巴胺用于表面修饰的研究进展

综述了多巴胺的聚合机理以及近年来聚多巴胺涂层分别作为一级和二级反应平台对材料表面进行修饰的研究进展情况,提出了多巴胺在橡胶与骨架材料的黏合领域应用的一些新设想。     

十二醇表面改性沉淀二氧化硅

选用十二醇作为改性剂对二氧化硅进行表面处理。讨论了改性剂用量、改性时间、改性温度等因素对改性效果的影响。由单因素实验得出优化工艺条件:改性剂十二醇用量为30 mL、10 g二氧化硅、1 g对甲苯磺酸、20 mL辅助溶剂二甲苯、改性时间为70 m in、改性温度为70℃,在此条件下改性后的产品的沉降体积为3.55 mL/g,活化度为92.85%,吸油值为2.53 mL/g,具有很好的疏水性。     

Surface modification and biological evaluation of kojic acid/silica nanoparticles as platforms for biomedical systems

Kojic acid (KA), an important compound with medical, cosmetic, and industrial applications, was loaded in 3-aminopropyltriethoxysilane-functionalized silica nanoparticle (MSNAPTES-KA5). This nanoparticle with acid was prepared to evaluate its application as a drug delivery system due to its interesting characteristic as large surface area, high pore volume, and good biocompatibility. The samples were characterized using different techniques that demonstrate success in the functionalization and loading process, as can be seen from the results obtained by FTIR, XPS, TGA, and CHN, that confirmed the presence of APTES and KA in the nanoparticles. KA drug loading was estimated using UV-Vis, TGA, and CHN, which revealed 12% loading of KA in the nanoparticles that showed slow rate of release. Antimicrobial assay was performed to evaluate the antimicrobial activity of the samples against different microorganisms. The results showed greater MSNAPTES-KA5 antibacterial activity than free-kojic acid for Candida albicans and Staphylococcus aureus. In relation to the acetylcholinesterase (AChE) inhibition assay; a higher inhibition of MSNAPTES-KA5, than the inhibition with free-kojic acid was observed. In addition, MSNAPTES-KA5 sample was also effective in inhibiting tyrosinase, proving the efficiency of the MSNAPTES base. These studies afford evidence of the possible beneficial biological activities of MSNAPTES-KA5 nanoparticle in pharmaceutical applications.     

Effect of silica modification on the chemical interactions in NBR‐based composites

Fillers are modified with the purpose of increasing their interactions with polymer matrices; however it is necessary to determine the impact that those modifications have on the composite performance and morphology. In this work, the strength of the chemical interactions between silica with different chemical characteristics and acrylonitrile butadiene rubber (NBR) is studied by infrared spectroscopy measuring the increase of C≡N fundamental vibration frequency and by density functional theory (DFT) and ab initio methods. The results from the chemical interactions were compared with the morphology and thermal behavior of composites based on those components. Good agreement between the molecular parameters estimated theoretically and the shifting of the absorption frequency due to C≡N stretching was observed. Morphological studies revealed that the steric hindrance exerted by modifier moieties on silica surface favors the filler dispersion. Functional groups on the surface strongly interacting with NBR play an important role in the compatibility of immiscible blends of NBR copolymers studied in this work. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

沉淀白炭黑的制备及表面改性

以液体硅酸钠和硫酸为原料，在室温下反应合成沉淀白炭黑，并用三甲基氯硅烷（TMCS）对其进行表面改性。采用正交实验设计法研究改性剂的用量、改性时间、改性温度、异丙醇的加入量等因素对改性效果的影响，得出适宜工艺为：改性剂用量为20％（质量分数），改性时问为90min，异丙醇用量为15mL，改性温度为98℃。在此条件下，改性产品亲油化度超过30％，得到疏水性良好的二氧化硅产品。     

纳米二氧化硅表面改性的研究

采用钛酸酯对纳米二氧化硅进行表面改性的研究,测定了改性样品的接触角,并用羟基紫外线吸收法测试了改性效果,对所得纳米样品的改性效果进行了评价。结果发现,钛酸酯与二氧化硅的比例为11%,在108℃条件下,以甲苯为溶剂反应1 h改性效果最好。     

Surface modification using bio‐inspired adhesive polymers based on polyaspartamide derivatives

The catechol functional group of dopamine (3,4‐dihydroxyphenethylamine) has the ability to form strong adhesive bonds to inorganic and organic surfaces in aqueous environments. In this study, novel adhesive polyaspartamides containing catechol pendant groups were synthesized from polysuccinimide through successive aminolysis reactions with quantitative dopamine and ethylenediamine. The adhesion and crosslinking of dopamine‐modified polyaspartamide in aqueous alkaline media was used successfully to modify the surface of various materials (including synthetic polymers, metals, metal oxides, ceramics) using a simple immersion method. Contact angle measurements, SEM and X‐ray photoelectron spectroscopy of the modified surfaces were used to verify the surface coating on a variety of materials with very different inherent wetting properties. These novel biocompatible polymers have potential industrial and biomedical applications as adhesives or coating materials for functional surface modification. Copyright © 2011 Society of Chemical Industry     

表面修饰对常压干燥SiO2气凝胶的研制

以正硅酸乙酯为硅源,采用溶胶-凝胶法常压下制备S iO2气凝胶。用比表面测定仪(BET),多功能衍射仪(XRD)和透射电镜(TEM)研究表明,S iO2气凝胶具有高比表面积和非晶纳米多孔结构;激光粒度分析仪表明,S iO2气凝胶平均粒子尺寸不足20μm,为介孔结构;表面化学修饰由傅里叶变换红外光谱仪(FTIR)进行确定;疏水性气凝胶(TG-DTA)的热稳定性测定从25—1 200℃进行了研究,研究表明:气凝胶的疏水性能维持到500℃;吸水性能分析结果进一步表明S iO2气凝胶具有非常好的疏水性。     

气相法白炭黑的表面改性

综述了近年来气相法白炭黑表面改性的研究成果和工业化技术。     

白炭黑表面改性对NR/BR硫化胶性能的影响

研究了10种偶联剂和3种表面活性剂改性白炭黑后对NR/BR硫化胶性能的影响.试验结果表明,不同表面改性剂改性白炭黑后对NR/BR硫化胶物理性能的影响程度大小顺序为硅烷类偶联剂＞钛酸酯类偶联剂＞表面活性剂.其中硅烷类偶联剂的改性效果优劣顺序为KH-550＞KH-846＞KH-590＞KH-560,带胺基和磷酸酯基团的偶联剂具有较好的抗老化作用;钛酸酯类偶联剂的改性效果优劣顺序为NDZ-311w＞NDZ-102＞NDZ-201＞NDZ-311＞NDZ-401＞NDZ-101;表面活性剂的改性效果优劣顺序为ATAC＞T-40＞ABS.