【作者】 沈玲；

【导师】 马育红；

【作者基本信息】 北京化工大学 ， 材料科学与工程， 2024， 硕士

【摘要】 通用塑料的高表面电阻使其易于累积静电,添加抗静电剂是提高其抗静电性能的最常用方法。但小分子抗静电剂存在抗静电效果不稳定和作用时间短等问题。本文以改善聚烯烃抗静电性能为目的,合成了多种含有羟基和羧基等活性基团的聚合物抗静电剂,考察了其对低密度聚乙烯（LDPE）和聚丙烯（PP）的抗静电性能和亲水性能的影响,试验发现羟基乙烯基醚和马来酸二烷基酯的交替共聚物能显著改善LDPE的抗静电性能和亲水性。在此基础上,系统地研究了不同羟基乙烯基醚和马来酸二烷基酯的共聚反应,以及共聚产物对LDPE性能的影响。主要研究内容及取得的成果如下:1、通过自由基共聚反应,合成了几种分子链中含羧基或羟基的共聚物,这些共聚物包括乙二醇单乙烯基醚（HEVE）和马来酸二甲酯（DMM）的共聚物（Poly（HEVE-alt-DMM））、新壬酸乙烯酯（VV-9）和马来酸酐（MAn）的共聚物（Poly（VV-9-co-MAn））、甲基丙烯酸缩水甘油酯与新癸酸加成物（MACE）和甲基丙烯酸（MAA）的共聚物（Poly（MACE-co-MAA））、以及新壬酸乙烯酯（VV-9）和甲基丙烯酸（MAA）的共聚物（Poly（VV-9-co-MAA））。考察了上述几种共聚物对LDPE和PP抗静电性能的影响,并与杜邦公司的Entira AS500和三洋化成的PELECTRON PVL进行了对比。结果表明,Poly（HEVE-alt-DMM）可以显著改善LDPE的抗静电性能和亲水性能。在添加了20 wt%的Poly（HEVE-alt-DMM）时,LDPE的表面电阻率为1.52×10⁷Ω,优于相同添加量的Entira AS500/LDPE共混物（3.41×10⁹Ω）和PELECTRON PVL/LDPE共混物（1.13×10⁸Ω）。其水接触角为75°,比纯LDPE降低了26°,在水中浸泡4周后仍保持在68°,具有优异亲水持久性。此外,Poly（HEVE-alt-DMM）/LDPE共混物（20/80）的拉伸强度为16 MPa,断裂伸长率为500%。同等添加量下,Entira AS500/LDPE和PELECTRON PVL/LDPE的拉伸强度分别为17 MPa和15 MPa,断裂伸长率为450%和470%。2、为了揭示羟基乙烯基醚和马来酸二烷基酯共聚物的结构与抗静电性能的关系,增加了二乙二醇单乙烯基醚（DEGV）和马来酸二丁酯（DBM）为共聚单体。研究了HEVE/DMM、HEVE/DBM和DEGV/DBM的共聚反应,这三个体系的单体总转化率分别为65.5%、58.6%和55.1%。相比于HEVE,DEGV与马来酸二烷基酯共聚物的数均分子量下降。采用ATR-FTIR和核磁共振谱图对共聚物结构进行了分析,证明合成的共聚产物为交替共聚物。对不同结构的聚（羟基乙烯基醚-马来酸二烷基酯）的性能进行了比较。实验结果显示,添加了20 wt%的Poly（HEVE-alt-DBM）、Poly（DEGV-alt-DMM）和Poly（DEGV-alt-DBM）的LDPE共混物的表面电阻率均等于或小于10⁸Ω,显著低于对照组纯LDPE(1.65×10¹³Ω)。在相同添加量时,不同羟基乙烯基醚和马来酸二烷基酯的共聚物与LDPE共混物的表面电阻率并无显著差异,共聚物中的羟基乙烯基醚亲水基团是抗静电的活性基团。改性后共混物的水接触角均低于对照组纯LDPE（101°）,其中,添加了20 wt%Poly（HEVE-alt-DBM）、Poly（DEGV-alt-DMM）和Poly（DEGV-alt-DBM）的LDPE共混物水接触角分别为91°、69°和67°,在水中浸泡4周后分别降低到68°、69°和49°,显示出了优异的亲水持久性。采用扫描电子显微镜（SEM）对共混物的微观形貌进行了表征,进一步分析了共混物的抗静电机理。DSC和TGA的实验结果表明,聚（羟基乙烯基醚-马来酸二烷酯）对LDPE共混物的结晶和熔点无显著影响。3.基于聚（羟基乙烯基醚-马来酸二烷酯）改性LDPE良好的亲水性,为了拓展亲水改性LDPE在生物医用材料领域的应用,考察了Poly（HEVE-alt-DMM）、Poly（HEVE-alt-DBM）、Poly（DEGV-alt-DMM）和Poly（DEGV-alt-DBM）改性的LDPE对细胞粘附和增殖的影响。分别通过CCK-8法和钙黄绿素（Calcein-AM）/碘化丙啶（PI）双染色法对细胞数量和细胞活性进行评估。结果表明,4种聚（羟基乙烯基醚-马来酸二烷酯）改性LDPE共混物无明显细胞毒性,可以支持细胞的生长和增殖,具有良好的生物相容性。更多还原

【Abstract】 General-purpose plastics are widely used in various fields due to their non-toxicity and affordability.However,the high surface resistance of plastics makes them prone to build-up electrostatic charge,resulting in susceptibility to static hazards during production and use.The most common way to improve the antistatic performance of polymer materials is to add antistatic agents.In this thesis a series of copolymers bearing-OH and/or-COOH groups was synthesized and evaluated as antistatic and hydrophilic modifiers of polyolefins,including low-density polyethylene（LDPE）and polypropylene（PP）.The preliminary results demonstrate that the alternating copolymers of hydroxyethyl vinyl ether and dimethyl maleate can significantly enhance the antistatic and hydrophilic performance of LDPE.1.A series of copolymers bearing-OH/-COOH groups were synthesized.These copolymers include the alternative copolymer of ethylene glycol monovinyl ether（HEVE）and dimethyl maleate（DMM）（Poly（HEVE-alt-DMM））,random copolymer of vinyl neodecanate（VV-9）and maleic anhydride（MAn）（Poly（VV-9-co-MAn））,the random copolymer of the adduct（MACE）of glycidyl methacrylate and methacrylic（MAA）（Poly（MACE-co-MAA））,and the random copolymer of VV-9 and MACE（Poly（VV-9-co-MAA））.Then,the antistatic and hydrophilic properties of these copolymers as LDPE and PP modifiers are tested with Entira AS500（Du Pont）and PELECTRON PVL（Sanyo Chemical）as benchmarks.The results demonstrated that Poly（HEVE-alt-DMM）can significantly enhance both the antistatic and hydrophilic properties of LDPE.With the addition of 20 wt%Poly（HEVE-alt-DMM）,the surface resistivity of LDPE blend is drastically reduced to about 1.52×10⁷Ωfrom the 1.65×10¹³Ωof pure LDPE.And it outperforms both Entira AS500/LDPE blend（3.41×10⁹Ω）and PELECTRON PVL/LDPE blend（1.13×10⁸Ω）at the similar loading.The water contact angle is 75°,which is 26°less than pure LDPE.After being immersed in water for 4 weeks,water contact angle remained as 68°.Furthermore,LDPE with a 20 wt%Poly（HEVE-alt-DMM）content exhibits a tensile strength of 16 MPa and an elongation at break of 500%.Under the similar addition,the control runs Entira AS500/LDPE and PELECTRON PVL/LDPE are 17 MPa and 450%,and 15 MPa and 470%,respectively.2.Encouraged by the above results,the comonomers of diethylene glycol monovinyl ether（DEGV）and dibutyl maleate（DBM）were also investigated by the copolymerization of HEVE/DMM,HEVE/DBM,and DEGV/DBM,resulting in overall conversions of 65.5%,58.6%,and 55.1%,respectively.The ATR-FTIR and NMR spectra of the copolymers supported that the products are alternating copolymers too.The results showed that,with 20 wt%of poly（hydroxyvinyl ether-dialkyl maleate）addition,the surface resistivities of the LDPE blends were equal to or less than 10⁸Ω,which were significantly lower compared to the pure LDPE(1.65×10¹³Ω).There was no significant difference in surface resistivity among the various blends,indicating that the antistatic properties of LDPE are mainly due to the presence of hydroxyl groups of hydroxy vinyl ether hydrophilic groups in the polymer.The water contact angles of the modified blends were all lower than that of the control of pure LDPE（101°）.Among them,the water contact angles of the LDPE blends with20 wt%Poly（HEVE-alt-DBM）,Poly（DEGV-alt-DMM）,and Poly（DEGV-alt-DBM）were 91°,69°,and 67°respectively,and were remained as 68°,69°,and49°after 4 weeks of immersion in water,which showed excellent hydrophilic persistence.Furthermore,characterized the microstructure of the blends by using scanning electron microscopy（SEM）,providing further insights into the anti-static mechanism of the blends.DSC and TGA results indicated that poly（hydroxyethyl vinyl ether-maleic acid diethyl ester）had no significant impact on the crystallization and melting points of the blends.3.Based on the excellent hydrophilicity of poly（hydroxyvinyl ether-dialkyl maleate）/LDPE,in order to expand the application of hydrophilic-modified LDPE in the field of biomedical materials,the effects of Poly（HEVE-alt-DMM）,Poly（HEVE-alt-DBM）,Poly（DEGV-alt-DMM）and Poly（DEGV-alt-DBM）modified LDPE on cell adhesion and cell proliferation were investigated.Cell number and cell activity were assessed by CCK-8 assay and Calcein-AM/propidium iodide（PI）double staining,respectively.The results demonstrated that poly（hydroxyvinyl ether-dialkyl maleate）/LDPE blends had no obvious cytotoxicity,could support cell growth and proliferation,and had good biocompatibility.更多还原