Properties And Composite Structures Of Attapulgite And Layered Double Hydroxide In Polymer Materials

In this thesis, several kinds of polymers (NBR, SBR, BR and PVC) and inorgainic nanoscale materials (attapulgite, montmorillonite and layered double hydroxide) were used to prepare polymer based organic/inorganic nanocomposites. The structures of the nanocomposites were inverstigated. The inorganic nanoscale materials were studied on the mechanical properties, solvent resistance, thermal stability, abrasion properties and dynamic mechanical properties of the nanocomposites.1. NBR/attapulgite (AT) nanocomposites and NBR/AT/Carbon Black (CB) nanocomposites were prepared by emulsion co-coagulation method with modified attapulgite. The oil-extended NBR/AT nanocomposites were firstly prepared. The attapulgite had the delayed curing characteristics. The attapulgite particles could enhance T90 time and reduce the cute rate. The extention of oil could enhance the cure rate of the nanocomposites. The nanoxomposites had the excellent mechanical properties, thermal stability, solvent resistance and dynamic mechanical properties. The results showed that the mechanical properties of nanocomposites improved as the increased of AT content with related lower amount of AT.2. By the interaction between montmorillonite and attapulgite, the nanometer composite of them were formed. A novel NBR/AT/MMT nanocomposite was prepared. The results of transmission electron microscope (TEM) indicated that the MMT and AT had the surface-surface interaction. This novel nanocomoposite had excellent mechanical properties.3. The oil-extended SBR1712/AT nanocomposites were prepared by emulsion co-coagulation method. The results of TEM indicated the attapulgite were nanoscale dispersed in the SBR1712 matrix. The mechanical properties of the nanocompistes could be improved with related lower amount of AT uesed. The oil-extended SBR1712/AT nanocomposites had excellent mechanical properties, solvent resistance and progressing performance. TGA analysis displayed that the thermal stability of oil-extended SBR1712/AT nanocomposites were enhanced in comparison with pure oil-extended SBR1712.4. The cis-1,4-polybutadiene rubber (BR)/organic montmorillonite (OMMT)/attpulgite (AT) nanocomposites were prepared by solution method. The structure of BR/OMMT/AT nanocomposites was studied by TEM. The mechanical properties, thermal stability and dynamic mechanical properties of BR/OMMT/AT nanocomposites were investigated. Based on 100 mL little reactor, the effect of recycled solvent on the conversion of butadiene polymerization. The results of TEM indicated that the OMMT and AT layers were dispersed in BR matrix on nanoscale. Compared with the pure BR, the tensile strength of BR/OMMT/AT nanocomposites increased by 600% when added 12 wt.% OMMT/AT (6 wt.%/6 wt.%). The conversion of butadiene polymerization was higher than 90% by using recycled solvent. The nanocomposites had excellent thermal stability. The dynamic mechanical analysis showed that Tg of BR/OMMT/AT nanocomposites shifted to higher temperature, and the nanocomposites had a good rolling resistance. The composites displayed better dynamic mechanical properties.5. Based on the previous research in our laboratory, a new Zinc-magnesium-aluminum layered double hydroxide (ZnMgAl-LDH) was prepared by one step co-precipitation using agents extracted from waste residue and intercalated with stearate anions. The X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectra showed that the stearate anions had successfully intercalated into the interlayer of ZnMgAl-LDH. The scanning electron microscopy (SEM) revealed the typical sand-rose morphology of layered double hydroxide. The enhanced thermal stability was confirmed by Congo red test. The PVC/ZnMgAl-LDH-stearate nanocomposites had much more thermal stability time than PVC and PVC/ZnMgAl-LDH composites. Thermal stability time of PVC containing 8 wt.% ZnMgAl-LDH-stearate loading was 12 times of that of pure PVC. The tensile strength of the nanocomposites increased with the increase of ZnMgAl-stearate content and exhibited excellent mechanical properties.