长烷基侧链对氟化甲基丙烯酸酯嵌段共聚物表面结构构筑的影响

【作者】 周斌；

【导师】 王新平； 杨菊萍；

【作者基本信息】 浙江理工大学 ， 高分子化学与物理， 2010， 硕士

【摘要】 以最低的氟化单体含量,得到最优异的表面疏水疏油性及最稳定的表面性质,是氟化高分子材料设计的理想目标。在课题组研究甲基丙烯酸丁酯（BMA）和甲基丙烯酸全氟辛基乙酯二嵌段共聚物（PBMA-b-PFMA）结构与性质的基础上,本论文首次合成了聚甲基丙烯酸丁酯-b-聚甲基丙烯酸十八酯-b-聚甲基丙烯酸全氟辛基乙酯（PBMA-b-PODMA-b-PFMA）、聚甲基丙烯酸丁酯-b-聚甲基丙烯酸十二酯-b-聚甲基丙烯酸全氟辛基乙酯（PBMA-b-PLMA-b-PFMA）三嵌段共聚物。利用接触角测试、X-射线光电子能谱（XPS）、衰减全反射红外光谱（ATR-IR）、X-射线衍射（XRD）、差示量热扫描（DSC）、动态光散射（DLS）、表面张力和和频振动光谱（SFG）等表征手段,研究了长烷基侧链的甲基丙烯酸酯类的引入对氟化丙烯酸丁酯嵌段共聚物表面性质、表面结构的影响。希望在此基础上加深理解聚合物表面结构与聚合物链结构的关系。得出以下结论:（1）当PBMA₁₆₄-b-PODMA_m-b-PFMA_n三嵌段共聚物中PFMA段长在3个单元以下时,随PODMA链长的增加,表面稳定性大大提高。在30℃水中浸泡达到平衡后,水和油的接触角下降值分别从两嵌段氟化聚合物的12.5°和20.2°减小到4.7°和7.6°。（2）当PBMA₁₆₄-b-PODMA_m-b-PFMA_n三嵌段共聚物中PFMA段长在3个单元以下时,随PODMA链长的增长,氟化组分在表面的富集程度增加,表明PODMA结晶可以推动含氟组分向表面离析;当PFMA段长在7个单元时,氟化组分在表面的富集程度与PODMA段的结晶关系不大,原因可能是PFMA段与PODMA段可以形成共晶,限制了氟化组分向表面的富集。（3）对于PBMA₁₆₄-b-PODMA₅₂-b-PFMA_n聚合物系列,氟化组分在表面的富集程度随PFMA段长的增加而下降,聚合物膜表面稳定性变差。（4）在PBMA₁₆₄-b-PFMA_n嵌段共聚物中引入聚甲基丙烯酸十二酯（PLMA）时,其表面氟化组分的富集程度远远低于引入聚甲基丙烯酸十八酯（PODMA）的氟化聚合物。（5）通过研究热处理PBMA₁₆₄-b-PODMA₁₀-b-PFMA_n膜发现,随PFMA段长的增加,氟化组分向表面的富集程度升高,氟化嵌段共聚物的层状结晶增强,膜表面稳定性提高。更多还原

【Abstract】 It is challenging to fabricate stable ?uorinated polymer surfaces with excellent water and oil repellent properties as well as low ?uorine content. On the basis of our previous work about surface properties and surface structures of poly（butyl methacrylate）–poly（perfluorooctylethyl methacrylate ） diblock copolymers, a series of poly（butyl methacrylate）-b-poly（octadecyl methacrylate）-b-poly（perfluorooctyl ethyl methacrylate）（PBMA-b-PODMA-b-PFMA） and poly（butyl methacrylate） -b-poly（lauryl methacrylate）-b-poly（perfluorooctylethyl methacrylate） （PBMA-b -PLMA-b-PFMA） were synthesized by atom transfer radical polymerization for the first time. In order to find the correlation of surface structure and the chain architecture of block copolymer, the influence of methacrylate with long side alkyl chain on the surface properties and surface structure of ?uorinated poly（butyl methacrylate） triblock polymers was investigated using contact angle measurement, X-ray photoelectron spectroscopy （XPS）, attenuated total re?ectance spectra of infrared （ATR-IR）, X-ray diffraction （XRD） , differential scanning calorimetry （ DSC）, dynamic light scattering （DLS）, surface tension and sum frequency generation （SFG） vibrational spectroscopy. Some conclusions were obtained as follows.（1） When the units of the PFMA were below 3 in poly（butyl methacrylate） -b-poly（octadecyl methacrylate）-b-poly（2-perfluorooctylethyl methacrylate） (PBMA₁₆₄-b-PODMA_m-b-PFMA_n), the stability of surface properties were enhanced with increasing length of the PODMA. The decrease of the water and oil contact angle on PBMA₁₆₄-b-PODMA₅₂-b-PFMA_1.43 films after immersed in 30℃water were 4.7°and 7.6°, respectively. But those on PBMA164-b-PFMA0.98 film surface were 12.5°and 20.2°, respectively.（2） When the units of the PFMA were below 3 in poly（butyl methacrylate） -b-poly（octadecyl methacrylate） -b-poly（2-perfluorooctyl ethyl methacrylate ） (PBMA ₁₆₄-b-PODMA_m-b-PFMA_n), the enrichment extent of fluorine on the film surface was increased with increasing the length of the PODMA block, which indicated that crystallization could drive migration of the perfluoroalkyl segment to the surface. But when the units of the PFMA was about 7, there was no correlation between the enrichment extent of fluorine and the length of PODMA. The PFMA block and the PODMA block might form mixed-crystallization, which reduced the migration of the perfluoroalkyl segment to the surface. （3） The enrichment extent of fluorine on the film surface and the surface stability of PBMA₁₆₄-b-PODMA₅₂-b-PFMA_n decreased with increasing the length of the PFMA block. The decrease in the water and oil contact angle on PBMA₁₆₄-b-PODMA₅₂-PFMA_1.43 after immersed in 30℃water were 4.7°and 7.6°, respectively. But those on PBMA₁₆₄-b-PODMA₅₂-b-PFMA_8.5 were 12.5°and 20.2°, respectively.（4） The enrichment extent of fluorine on the surface of PBMA₁₆₄-b-PLMA_m- b-PFMAn film was much lower than that of PBMA164-b- PLMA_m-b-PFMA_n films.（5） The enrichment extent of fluorine and the layered structure of the fluorinated side chains on the annealed film surface of PBMA₁₆₄-b-PODMA₁₀-b-PFMA_n was enhanced greatly. Accordingly, the film surface became more stable with increasing length of the PFMA.更多还原