scholarly journals Supramolecular exfoliation of layer silicate clay by novel cationic pillar[5]arene intercalants

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Takahiro Kakuta ◽  
Yudai Baba ◽  
Tada-aki Yamagishi ◽  
Tomoki Ogoshi

AbstractClays are multi-layered inorganic materials that can be used to prepare nanocomposite fillers. Because the multi-layered structure is thermodynamically stable, it is difficult to change a multi-layered material into single layers to improve its dispersity. Previously, clays were modified with dodecylammonium cations to promote complexation with nylon 6, nylon 66, polypropylene, polyethylene, polystyrene, and polycaprolactone to increase the mechanical strength (and/or thermal stability) of the composite material; however, complete exfoliation could not be achieved in these composites. In this study, pillar[5]arenes are synthesized and functionalized with ten cationic substituents as novel intercalants for modifying bentonite clay, which is a multi-layered metal-cation-containing silicate. The pillar[5]arenes exfoliate the clay by forming polyrotaxanes with poly(ethylene glycol) through host–guest interactions.

2016 ◽  
Vol 13 (2) ◽  
pp. 221-234
Author(s):  
Baghdad Science Journal

Different polymers were prepared by condensation polymerization of sebacic anhydride and adipic anhydride with ethylene glycol and poly(ethylene glycol). Their number average molecular weights were determined by end group analysis. Then, they were grafted on the prepared phthalocyaninatocopper(II) compounds with the general formula (NH2)4PcCu(II) having amino groups of 3,3',3'',3'''- or 4,4',4'',4'''- positions. All prepared polymers, compounds, and phthalocyaninatocopper(II)-grafted polymers were characterized by FTIR. The sizing measurements were carried out in 3,3',3'',3'''- (NH2)4PcCu(II) and 4,4',4'',4'''- (NH2)4PcCu(II) compounds with and without grafting polymers. The results showed that the grafting process led to decreasing in particle size and increasing in surface area. The grafting process was reflected positively on the thermal degradation of 3,3',3'',3'''- (NH2)4PcCu(II) and 4,4',4'',4'''- (NH2)4PcCu(II) grafted polymers. They had higher thermal stability accompanied with higher char residue and T50% weight loss with 3,3',3'',3'''-(NH2)4PcCu(II) and their grafted polymers being the best.


e-Polymers ◽  
2008 ◽  
Vol 8 (1) ◽  
Author(s):  
Puyu Zhang ◽  
Lichao Peng ◽  
Wenbin Li

AbstractIonic liquid [bmim]PF6 (1-butyl-3-methylimidazolium hexafluoro phosphate) was synthesized and characterized. It was used as the plasticizer for poly(L-lactide) (PLLA). The glass transition temperature (Tg) and the thermal stability of the plasticized PLLA samples were measured by thermogravimetry (TG) and differential scanning calorimetry (DSC). Compared with poly(ethylene glycol) having Mw of 300 g/mol (PEG300), TG results showed that the thermal stability of PLLA plasticized with ionic liquid was better than that of PLLA plasticized with PEG300. The Tg of plasticized PLLA decrease with increasing the content of ionic liquid [bmim]PF6 from 2 wt.% to 10 wt.%. The Tg of PLLA can be reduced to 40°C when the content of ionic liquid [bmim]PF6 was 10 wt.%. The materials of PLLA with plasticizer were also investigated using polarizing microscope (POM), the results of which indicate that the movements of PLLA chains were improved when ionic liquid plasticizer was used.


Polymers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 728
Author(s):  
Sangyoon Park ◽  
Sarinthip Thanakkasaranee ◽  
Hojun Shin ◽  
Youngsoo Lee ◽  
Guman Tak ◽  
...  

To improve the dimensional thermal stability of polyethylene terephthalate (PET), a poly(ethylene glycol 1,4-cyclohexane dimethylene (CHDM) isosorbide (ISB) terephthalate) (PEICT) known as ECOZEN®T110 (EZT) was introduced into PET using a melt blending technique. The miscibility, morphology, and thermal properties of the PET/EZT samples were investigated. The introduction of amorphous EZT into semi-crystalline PET increased the glass transition temperature (Tg) but decreased the crystallinity, which could be related to the transesterification reaction. By adding EZT contents up to 20%, the PET/EZT samples showed a single Tg, which indicated the miscibility between PET and EZT. However, two Tg values were observed in the PET/EZT samples with higher EZT contents (30–70%), indicating partial miscibility. This may have been due to the slightly different rheological and thermodynamic parameters that were affected by a higher ratio of bulky (rigid ISB and ductile CHDM) groups in EZT. However, the heat distortion temperature of the PET/EZT samples remarkably increased, which indicated that the dimensional stability was truly enhanced. Although the crystallinity of the PET/EZT samples decreased with increasing EZT content, the tensile strength and Young’s modulus decreased slightly. Based on these results, the as-prepared PET/EZT samples with high dimensional stability can be used as a high-temperature polymeric material in various applications.


2008 ◽  
Vol 109 (6) ◽  
pp. 4112-4120 ◽  
Author(s):  
Xuepei Yuan ◽  
Chuncheng Li ◽  
Guohu Guan ◽  
Yaonan Xiao ◽  
Dong Zhang

2015 ◽  
Vol 1102 ◽  
pp. 125-128
Author(s):  
Hua Ti Li ◽  
Dong Liu ◽  
Ying Li ◽  
Jie Lin Wang ◽  
Xia Wang

The organic ligand 2-Thenoyltrifluoroacetone (TTA) which was selected as molecular bridge for sensitization of europium and terbium ions were modified by 3-(triethoxysilyl)-propylisocyanate (TEPIC) to obtain the hybrid precursor TTA-Si. Then the solution of Eu(NO3)3 and Tb(NO3)3 were added in the presence of tetraethylorthosilicate (TEOS). The binary lanthanide organic/inorganic hybrid material were obtained. The ternary hybrid materials were obtained by adding the solution of Eu(NO3)3 and Tb(NO3)3 and Poly (ethylene glycol) (PEG400). We investigated the thermal stability and luminescence properties of hybrids and found that the ternary hybrid materials exhibit better thermal stability and stronger emission intensity. Furthermore, compared with the binary mesoporous material Eu-(TTA-Si)3 and Tb-(TTA-Si)3, the ternary mesoporous material Eu-(TTA-Si)3-PEG and Tb-(TTA-Si)3-PEG exhibits the characteristic emission of the Eu3+ and Tb3+ ion with a higher luminescence intensity, suggesting that the introduction of PEG is of benefit for the sensitization of Eu3+ and Tb3+ luminescence, by replacing H2O groups that can quench the luminescence of Eu3+ and Tb3+ ions.


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