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In this work, a strategy was used to combine Mg(OH)2 nanoparticles (MDH), the bentonite nano‐sheets, and melamine cyanurate (MC) to prepare dioctyl phthalate (DOP) plasticized polyvinyl chloride (PVC) nanocomposites with increased thermal stability, Limiting Oxygen Index (LOI), and tensile strength as well as reduced total heat release. To prepare MC‐modified Mg(OH)2@bentonite nanohybrid (MMHB), MDH was installed on the calcined bentonite and consequently modified with MC. The nanocomposite thin films were prepared from plasticized‐PVC and MMHB using the solvent casting method. It was found that the combination of MDH and the bentonite nano‐sheets in the presence of MC could improve the PVC properties. Thermogravimetric analysis (TGA) in both N2 and air atmospheres, indicated that the thermal stability of PVC was enhanced via adding MMHB, which was evident by the increased thermal decomposition temperature. The microscale combustion calorimetry (MCC) results of the PVC nanocomposites with 5% and 8% by mass of MMHB revealed that an optimal isolating layer is formed, which increased flame retardant properties. The PVC matrix nanocomposite containing 8% by mass of MMHB with LOI value of 33.4% exhibited high flame retardancy. Moreover, the tensile strength and elastic modulus of the sample containing 5% by mass of MMHB increased by 65.5% and 55.2% compared to those of pristine PVC, respectively. Highlights: A nanohybrid was prepared from Mg(OH)2 (MDH) and calcined bentonite.Preparation of melamine cyanurate (MC).Preparation of MC‐modified MDH@bentonite nanohybrid (MMHB).Effects of MMHB on thermal stability and flame retardancy of plasticized PVC.The efficient flame retardancy effect of the additive on plasticized PVC. [ABSTRACT FROM AUTHOR]

A tetra-ester (TE) functionalized organic compound was synthesized for the restoration the mechanical properties of the PVC/Mg(OH)2 nanocomposites. The organically modified Mg(OH)2 nanoparticles (OMN) were prepared by surface modification of Mg(OH)2 nanoparticles (MDH) using a methylated tetra-phenol (TP) organic compound to achieve the homogeneous MDH distribution in the nanocomposite matrix. The results of FT-IR, XRD, and FE-SEM revealed the successful surface treating of MDH. The PVC nanocomposites were prepared by solvent blending and casting method. From the TGA analyses, the 10% mass loss temperature and the char yield of PVC containing 3% by mass of OMN and 3% by mass of TE, in N2 atmosphere, increased by 13 °C and 7%, respectively, compared to unfilled PVC. From the microscale combustion calorimeter, a decreasing heat release rate from 125.2 to 92.8 W g–1 was observed for PVC film filled with 6% by mass of each additive, compared to unfilled PVC. The tensile test results revealed that TE and OMN have been effective for the improvement of the PVC tensile strength. For example, incorporating only 6% by mass of each filler led to an improvement in tensile strength from 58.99 to 80.58 MPa, compared to unfilled PVC. [ABSTRACT FROM AUTHOR]

New type of aromatic polyamide/montmorillonite nanocomposites were produced using solution process in N-methyl-2-pyrolidone. Amide chains were synthesized from 4,4′-diaminodiphenyl sulfone and p-phenylenediacrylic acid in N-methyl-2-pyrolidone. The resulting nanocomposite films containing 5–15 mass % of organoclay were characterized for FT-IR, scanning electronmicroscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), optical transparency and water absorption measurements. The distribution of organoclay and nanostructure of the composites were investigated by (XRD) and SEM analyses. Thermogravimetric analysis indicated an increase in thermal stability of nanocomposites as compared to pristine polyamide. The percentage optical transparency and water absorption of these hybrids was found to be much reduced upon the addition of modified layered silicate indicating decreased permeability.

New poly(amide-imide)-montmorillonite reinforced nanocomposites containing Bis(4-N-trimellitylimido) diphenyl ether moiety in the main chain were synthesized by a convenient solution intercalation technique. Poly(amide-imide) (PAI) 4 was synthesized by the direct polycondensation reaction of Bis(4-N-trimellitylimido) diphenyl ether 3 with 4,4′-diamino diphenyl ether 2 in the presence of triphenyl phosphite (TPP), CaCl2, pyridine and N-methyl-2-pyrrolidone (NMP). Morphology and structure of the resulting PAI-nanocomposite films 4a and 4b with 10 and 20 mass% silicate particles respectively, were characterized by FT-IR spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The properties of nanocomposites films were investigated by using Uv-vis spectroscopy, thermogravimetric analysis (TGA) and water uptake measurements.