Crystallinity index is used to estimate the order of the kaolinite and it is the important factor of the intercalation,but there were some exception in service. The relative intensity of the functional groups (Si-O, O-H) of the kaolinite with different crystallinity index (HI=1.25, 0.71, 0.52 and 0.18) were analysed by the IR spectra of the functional groups to include the relation between the microstructure of the interlayer and the crystallinity index. In the presented experiments,the kaolinite+N-methylformamide intercalates were investigated to research the relation btween the microstructure and the intercalation. The results indicated that the relative intensity of 3696cm-1 was consistent with the order of the HI. And the bands of OH and Si-O groups had definite rules. Longyan kaolinite with the maximal difference of Si-O(540cm-1,471cm-1 and 432cm-1) bands had the biggest intercalation rate which was up to 99.8%. Datong kaolinite with the minimal difference of Si-O had the opposite characteristic to the Longyan kaolinite. It indicated that it is limited to imply the degree of intercalated action only depending on the HI index,however, it was exact to imply it to combine the crystallinity index and the relative intensity of the functional groups.
Sepiolite was purified and modified with hydrochloric acid,then modified with cetyl trimethyl ammonium bromide(CTAB) to get organic sepiolite.X-ray diffraction,fourier transform infrared spectroscopy(TFIR) and scanning electron microscopy(SEM) were used to analyze the samples.The results showed that impurities such as calcite were removed from the sepiolite,some of Mg in the sepiolite was replaced by H,and the structural water which coordinated with the end position Mg was removed.The layer spacing of sepiolite expanded from 12.16 nm to 12.30 nm by organic modification and it is advantageous for sepiolite fiber bundle separation.
Taurine layered double hydroxide(TAU-LDH) and ibuprofen layered double hydroxide(IBU-LDH) were prepared with calcinated-hydration method,by using taurine(TAU) and ibuprofen(IBU) as interlayer anions.XRD and FT-IR were used to characterize the structure of intercalation compounds.Drug release characteristics of TAU-LDH and IBU-LDH were investigated with a dissolution test in a phosphate buffer dissolution(PBS).The UV-Vis test results show that the drug release in the interlayer of LDHs is a slow process.TAU-LDH compound releases 85% of TAU in 40 min and 100% of TAU in 180 min,while IBU-LDH compound releases 88% of IBU in 40 min and 100% of IBU in 180 min.This data suggested that these drug-inorganic hybrid materials can be used as an effective drug delivery system.
Mg-Al phase layered double hydroxide(LDH) was prepared by co-precipitation method,and Mg-Al layered double oxide(LDO) is prepared by calcination LDH under the temperature of 400-550 ℃.LDO is used as start material to study phenol removal and the influence factors including calcined temperature of LDH,adsorption time and LDO dosage.The phenol removal and mechanism are characterized by the technologies of XRD,FTIR,BET and UV spectrophotometer.The results show that the removal ratio of phenol can reach 67% when dosage of LDO is 5 g/L,the adsorption equilibrium time is 4 h,the original phenol concentration of wastewater is 0.1 g/L.The main adsorption mechanism is the intercalation of phenol anion in the interlayer of LDO to form LDH.Some phenol is adsorbed on the surface of LDO.
The flame retardant characteristics of PP/MMt nanocomomposites,included the preparation methods,the characterization microstructures,analytical techniques of flame retardant,and also the burning behavior and the mechanism of flame retardant were reviewed.Some unsolved problems and development potentials for this flame retardant approach were presented.
Sintering-expanded haydite has been prepared by using red mud with glasses,fly ash and a little of other additive.The results show that the content of red mud and firing temperature ore main factors influencing the performances of haydite.The single grain compressive strength of haydite is 0.6kN,water absorption is 0.4% and apparent density is 1.31g/cm3 when the firing temperature is 1140℃ and the content of red mud is 50wt%.The haydite has very good glazy surface structure with closed pore structure.The main components of haydite are hematite,hibschite,anorthite,perofskite,nephline and vitreous.
Flame retarded unsaturated polyester resin/supramolecular hydrotalcite composite was prepared by using supramolecular hydrotalcite(LDH-PTS).The change of the supramolecular hydrotalcite interlayer spacing was studied by means of XRD,the flame retardance of the composite was studied by means of TG method,LOI test and horizontal burning test,and the mechanical properties of the composite were also tested.The results showed the interlayer spacing of LDH increased from 1.73 nm in LDH-PTS to 2.077 nm in the composite.Compared with unsaturated polyester resin,the addition of 3%(mass fraction)of LDH-PTS improved the flame retardance remarkably,LOI increased from 21% to 23.30 %,T50% rose from 390.3℃ to 400.3 ℃,char residue rate increased by 3.7%,the speed of horizontal burning decreased by 20.24%,while the tensile strength of the composite was basically same with that of unsaturated polyester resin.
Silver particles were prepared by using the kaolinite-dimethyl sulfoxide as precursor and PVP as dispersant,and by interlaminar substitution of silver-ammino complex.The kaolinite interlamination was used as a reactor to control the silver particle size for the preparation of kaolinite-sliver intercalation complex.XRD pattern indicates that PVP modifies surface of the kaolinite and promotes synthesis of Ag particles in the kaolinite interlayers.Four diffraction peaks of Ag were observed.The(001) peak of small angle X-ray diffraction showed that the basal spacing of kaolinite increases from 0.716nm to 4.53nm.The morphology of Ag in the kaolinite interlamination was obsevered by TEM.
