论文题目：OP1314/DOPO-SiO2复配阻燃PA6材料的制备及其机理研究

毕业学生：李茂林

指导教师：吴唯

中文摘要：

本文研究了PA6/AlPO₄, PA6/MCA, PA6/OP1314阻燃材料的阻燃性能。其中当阻燃剂OP1314的质量分数为20%时，PA6/OP1314阻燃材料能达到UL 94 V-0（1.6mm）等级，LOI值为30±0.5%, 在TGA测试中，相比于纯PA6材料，PA6/OP1314材料的最大降解速率降低了，在700℃时残余率为6.4wt.%。但是进一步分析发现，残炭在扫描电镜下炭层不规整，表面呈现多处缺陷和孔洞。

通过加入合成的DOPO-SiO₂到PA6/OP1314后发现，质量分数为5%的DOPO-SiO₂能显著增强PA6/OP1314的阻燃性能。材料能达到UL 94 V-0 （1.6mm）级别，LOI值为32±0.5%；在TGA测试中，最大降解速率相对于PA6/OP1314体系有所降低，在700℃时残余率为12.0 wt.%；在扫描电镜下的炭层形状规整，表面光滑紧实，没有缺陷；而且通过能谱仪的成分分析显示PA6/OP1314/DOPO-SiO₂ 残炭的含碳量最高，说明DOPO-SiO₂的加入能在基体外形成一层屏障，隔绝与外界的空气与热流交换。另外，通过用高级旋转流变仪分析PA6，PA6/OP1314，PA6/OP1314/DOPO+SiO₂，PA6/OP1314/DOPO-SiO₂的粘弹性，发现PA6/O1314/DOPO-SiO₂的储能模量和粘度都高于其它体系，说明PA6/O1314/DOPO-SiO₂体系的相容性好。

最后对PA6/OP1314/DOPO-SiO₂阻燃体系的阻燃机理进行研究。先将PA6和PA6/OP1314/DOPO-SiO₂在同一残余率不同温度下的马弗炉中放置15min，残余物用傅里叶红外测试。然后分别用热裂解质谱测试PA6 , PA6/OP1314, PA6/OP1314/DOPO-SiO₂。分析得知在气相中，PO·, PO₂· 和P₂O₄·充当捕获剂，减少和消除参与燃烧反应的自由基;三聚氰胺能产生N₂, NH₃, 和H₂O来稀释可燃性气体。在固相中，三聚氰胺的裂解产物和磷酸盐能与PA6的裂解产物发生交联反应，形成交联结构来提高材料的热稳定性；SiO₂也能起到物理屏障的作用，隔绝与外界的气体和热量交换。通过对PA6 , PA6/OP1314, PA6/OP1314/DOPO, PA6/OP1314/SiO₂, PA6/OP1314/DOPO-SiO₂的热分析得知，PA6/OP1314/DOPO-SiO₂体系的热降解活化能最高，而且随着反应进度α的增加，PA6/OP1314/ DOPO-SiO₂体系的热降解活化能也在逐渐增加，说明在后期的降解过程越来越难。

  Abstract:

The article studied the flame retardant of PA6/AlPO₄, PA6/MCA, PA6/OP1314. With the loading of 20wt.% OP1314,  PA6/OP1314 achieved a vertical burning test V-0 (1.6mm) rating and a limiting oxygen index (LOI) value 30%. In the test of TGA, The maximum mass loss rate of decomposition decreased significantly and char residue increased to 6.8 wt.% compared with that of pure PA6 at the temperature of 700℃. But, the morphology of char was not uniform and existed lots of flaws and holes on the surface.

When 5wt.% DOPO-SiO₂ was added into the PA6/OP1314, the composite PA6/OP1314 achieved a vertical burning test V-0 (1.6mm) rating and a limiting oxygen index (LOI) value 32%. In the test of TGA, The maximum mass loss rate of decomposition decreased and char residue increased to 12.0 wt.% compared with that of PA6/OP1314 at the temperature of 700℃. The morphology of char was uniform, compact and smooth on the surface. The result of EDS showed that the carbon content of PA6/OP1314/DOPO-SiO₂ was the highest, suggested that a barrier was formed to isolating the gas and heat transferring with the addition of DOPO-SiO₂. Futhermore, The storage modulus and complex viscosity of PA6/OP1314/DOPO-SiO₂ was the highest, demonstrated that PA6/OP1314/DOPO-SiO₂ exhibited high compatibility .

Finally, The flame-retardant mechanism of  PA6/OP1314/DOPO-SiO₂ was also investigated and for that the residues from the samples of the composite that were submitted to different temperatures were investigated through FTIR and the pyrolysis product was also demonstrated by pyrolysis gas chromatography/mass spectrum (Py-GC/MS). In the gaseous phase, hypophosphite and DOPO-SiO₂ produced PO·, PO₂· and P₂O₄· radicals to capture active radicals and terminate the radical reaction, while melamine released N₂, NH₃ and H₂O to dilute the combustible gases. In the condensed phase, the phosphate and melamine reacted with the degradation products of PA6 to form cross-linked structures, while the generated SiO₂ acted as a physical barrier on the surface of the matrix to insulate the transfer of heat and oxygen. With the thermal analysis of PA6, PA6/OP1314, PA6/OP1314/DOPO, PA6/OP1314/SiO₂, PA6/OP1314/ DOPO-SiO₂, the thermal degradation activation energy (E) of PA6/OP1314/DOPO-SiO₂ was the highest. And the E growed with the α, suggested its degradation would be increasingly hard.

论文题目：凹凸棒土的改性及其对软质PVC增塑剂迁移和阻燃性的影响

毕业学生：朱松伟

指导教师：吴唯

中文摘要：

本文为改善软质PVC材料的增塑剂迁移以及阻燃性，采用了添加纳米凹凸棒土制备纳米复合材料的方法。凹凸棒土(ATP)属于一维的天然纳米材料，表面极性大，吸附性强，但亲水性强、易团聚，与有机基体亲和力弱。因此将凹凸棒土应用到PVC材料之前其表面往往会经过有机化改性处理。本研究先采用硅烷偶联剂ATPES对ATP表面进行一次改性，引入-NH₂基团，再在一次改性基础上加入硬脂酸，对ATP进行复合改性处理；再将不同改性的ATP以不同比例添加到软质PVC体系和软质阻燃PVC体系中，表征了ATP对软质PVC的增塑剂迁移性、力学以及热稳定性等性能的影响，并分析了改性ATP对软质PVC的增塑剂迁移抑制作用及在软质阻燃PVC体系中协效阻燃的机理。

通过对改性凹凸棒土进行红外光谱分析（FTIR）、热重分析（TGA）、接触角及比表面积（BET）等测试研究发现，硅烷偶联剂ATPES和硬脂酸均在ATP表面成功修饰，5g ATP在3.0g ATPES和3.9g硬脂酸条件下对其改复合性效果最佳，此条件下复合改性ATP疏水亲油性增加、几乎完全疏水，且孔径增大。

改性ATP对软质PVC中增塑剂迁移影响明显，添加2 phr 复合改性ATP的软质PVC在环己烷溶剂中浸泡5天后的增塑剂抽出率比原软质PVC降低了10.3%，同时，拉伸强度和断裂伸长率也分别提高了13.1%和25.1%。凹凸棒土对软质PVC的阻燃性能虽无明显影响，但1 phr复合改性凹凸棒土却使磷酸酯型软质阻燃PVC体系的氧指数升高、垂直燃烧时间缩短等，表现出优良的协效阻燃性。

  Abstract:

The flexible PVC/attapulgite nano-compsites were prepared by melt blending to improve the plasticizers migration and flame retardancy of flexible PVC. Attapulgite clay(ATP) is a kind of one-dimensional silicate mineral，with the characteristics of a high specific surface area and strong adsorption. But ATP used to be modified because its good hydrophilia. To prepare the hydrophobic property of attapulgite nanoparticles, steric acid was introduced as complex modifier to react with -NH₂ on the surface of ATP after the the process with silane coupling agent ATPES. Then the modified ATP was added into flexible PVC in different quantity to analyzed its effects on the plasticizers migration , mechanical properties, flame retardancy of flexible PVC.

The modified ATP were characterized with Fourier transform infrared analysis ( FTIR) , contact angle tests and thermal gravimetric analysis(TGA). The results showed that the ATP was successfully modified by the organic modifiers and 5g ATP can achieve best modification effect under the conditions of 3g ATPES and 3.9g stearic acid. The hydrophobic property and the pore size of ATP modified with complex modifier improved much.

Besides, the addition of 2 phr ATP modified by complex modifier not only reduced the plasticizer extraction rate by 10.3% compared to the original PVC, but also the tensile strength and elongation at break of PVC increased by 13.1% and 25.1%. Although the ATP made no difference to the flame retardancy of flexible PVC, 1 phr ATP modified by complex modifier exhibited good synergism of flame retardancy that the limit oxygen index of PVC was increased and the vertical burning time was reduced.

论文题目：TPEE 基吸水膨胀弹性体的相容性及耐盐性研究

毕业学生：李宁

指导教师：吴唯

中文摘要：   

  Abstract: