發(fā)布時(shí)間：2018-04-18 13:51

  本文選題：ATRP + 納米復(fù)合微粒��； 參考：《河北科技大學(xué)》2011年碩士論文

【摘要】：原子轉(zhuǎn)移自由基聚合(ATRP)技術(shù)作為一種新穎的聚合方法,是實(shí)現(xiàn)“活性”/可控聚合的有效途徑,將ATRP技術(shù)用于無(wú)機(jī)納米粒子的表面接枝聚合改性,既能充分發(fā)揮“活性可控”的特點(diǎn),又能使產(chǎn)物兼具有機(jī)/無(wú)機(jī)材料的特點(diǎn)。 本研究首先以水為反應(yīng)介質(zhì),通過(guò)細(xì)乳液聚合工藝采用原子轉(zhuǎn)移自由基聚合法制備了分子量分布窄的聚合物粒子。研究了水體系中的原子轉(zhuǎn)移自由基聚合工藝,探討了可控反應(yīng)機(jī)理并考察了其反應(yīng)特點(diǎn)；研究了不同類型乳化劑、不同分子結(jié)構(gòu)的配體對(duì)水體系A(chǔ)TRP反應(yīng)穩(wěn)定性和可控性的影響；優(yōu)化了水體系中ATRP反應(yīng)的工藝條件和工藝參數(shù)。結(jié)果表明：采用細(xì)乳液工藝進(jìn)行ATRP反應(yīng)要比常規(guī)乳液體系中的可控性較好；催化劑在油水兩相中的分配對(duì)反應(yīng)的可控性有較大的影響；當(dāng)采用非離子型乳化劑TW-80時(shí),其乳化劑用量為15.4%(g/g-St)、助乳化劑用量為3%、催化體系(CuCl/dNbpy)的用量為0.15(mol/mol-St),反應(yīng)溫度為75℃時(shí),反應(yīng)體系的穩(wěn)定性及可控性較好,并且聚合物的分子量隨單體轉(zhuǎn)化率的增大呈線性增長(zhǎng)趨勢(shì),分子量的大小可通過(guò)單體與引發(fā)劑的比例來(lái)調(diào)控。通過(guò)GPC、FI-IR、TEM、SEM、激光粒度分布儀、TGA等對(duì)所制備的聚合物進(jìn)行了表征,結(jié)果表明：聚合物的分子量分布較窄(Mw/Mn=1.32),乳膠粒粒徑分布均勻約為200nm左右,為規(guī)則的球形。 在上述工藝研究基礎(chǔ)上,采用原子轉(zhuǎn)移自由基聚合法制備了納米SiO2/PSt復(fù)合乳液粒子。首先對(duì)納米粒子表面進(jìn)行了改性,將ATRP引發(fā)劑接枝到納米粒子表面,采用ATRP法制備了接枝型納米SiO2/聚合物復(fù)合粒子,并對(duì)其進(jìn)行了分析表征,結(jié)果表明：硅烷偶聯(lián)劑分子可與納米SiO2表面的羥基反應(yīng),其改性和接枝的溫度分別為65℃和70℃,負(fù)載率和接枝率最高分別可達(dá)到21%和12%；當(dāng)SiO2-Cl與單體的用量比例為0.06(g/g)、反應(yīng)溫度為75℃時(shí),所合成的接枝型納米SiO2/PSt復(fù)合乳液的轉(zhuǎn)化率為85%,接枝效率最高可達(dá)81%,復(fù)合乳液穩(wěn)定性較好,其聚合物的分子量分布較窄(Mw/Mn=1.34)。通過(guò)TGA分析,納米SiO2/PSt的熱分解溫度要比純聚苯乙烯的熱分解溫度高約40℃,可有效地提高材料的耐熱性能。
[Abstract]:As a novel polymerization method, atom transfer radical polymerization (ATRP) is an effective way to realize "active" / controllable polymerization. ATRP technology is used to modify the surface of inorganic nanoparticles by grafting polymerization.It can not only give full play to the characteristics of "activity controllable", but also make the product have the characteristics of organic / inorganic materials.In this study, polymer particles with narrow molecular weight distribution were prepared by atom transfer radical polymerization with water as reaction medium.The atomic transfer radical polymerization process in water system was studied, the controllable reaction mechanism and reaction characteristics were investigated, the effects of different emulsifiers and ligands with different molecular structures on the stability and controllability of ATRP reaction in water system were studied.The process conditions and parameters of ATRP reaction in water system were optimized.The results show that the ATRP reaction with fine emulsion process is better than that in the conventional emulsion system, the distribution of catalyst in oil-water phase has a great influence on the controllability of the reaction, and when the non-ionic emulsifier TW-80 is used, the controllability of the reaction is greatly affected by the distribution of catalyst in the oil-water two-phase system.The amount of emulsifier is 15.4g / g-Sti, the dosage of co-emulsifier is 3um, the amount of catalytic system CuCl-dNbpyy is 0.15kmol / mol -Sti, the reaction temperature is 75 鈩，

本文編號(hào)：1768631