偏氯乙烯共聚物/纳米水滑石复合材料及多孔炭的制备与表征

Preparation and characterization of vinylidene chloride copolymer/nanometer hydrotalcite composites and porous carbons

采用原位悬浮聚合和熔融加工制备了不同纳米水滑石含量的偏氯乙烯-丙烯酸甲酯（VDC-MA）共聚物/纳米水滑石复合材料,并通过高温炭化和模板消除得到多孔炭材料。采用电镜、X射线衍射、N2吸脱附法表征了复合材料和多孔炭的结构。结果表明,纳米水滑石含量≤6.25%（质量）时,纳米水滑石基本以初级粒子均匀分散在VDC-MA共聚物基体中,并在炭化过程中转化为金属氧化物;金属氧化物可经酸洗去除,起到模板致孔作用;同时VDC-MA共聚物炭化过程形成大量微孔,因此得到的多孔炭具有微孔和中孔分布。当炭化温度较低时（600~700℃）,VDC-MA共聚物炭化不完全,得到的多孔炭的比表面积和孔容较低;当炭化温度为800℃时,由不同水滑石含量的VDC-MA共聚物复合材料制备的多孔炭比表面积为1000 m2.g-1左右,由水滑石含量为6.25%（质量）的复合材料制备的多孔炭的中孔率最高,达26.5%。

To prepare porous carbons with meso-pores,nanometer hydrotalcite（HT）particles were incorporated into vinylidene chloride-methyl acrylate（VDC-MA）copolymer by in-situ suspension polymerization and further melt processing.Porous carbons with meso-pores were obtained by high-temperature carbonization of the VDC-MA copolymer/HT composites and removing of inorganic particles.The composites and the resultant porous carbons with meso-pores were characterized by electron microscope,X-ray diffraction,and nitrogen adsorption/desorption analysis.The results showed that most HT particles were dispersed in the VDC-MA copolymer matrix in nanometer size,when the mass fraction of HT was ≤6.25%.HT was transformed to metal oxides during the carbonization process,which was easy to remove by acid etching and acted as template to form meso-pores.During the carbonization process,micro-pores were also formed due to the thermal degradation of VDC copolymer.When carbonization temperature was lower（600—700℃）,VDC-MA copolymer could not be degraded completely,and the specific surface area and porosity of the resulted carbon were lower.When carbonization temperature was 800℃,the carbons prepared from composites with different HT contents had specific surface areas of about 1000 m2·g-1.The maximum degree of meso-porosity was 26.5% for the carbon prepared from VDC-MA copolymer/HT composite with 6.25%（mass） HT.