Recycled PET nanocomposites improved by silanization of organoclays

Abstract

Recycled PET/organo-modified montmorillonite nanocomposites were prepared via melt compounding as a promising possibility of the used beverage bottles recovery. According to our previous work, the three suitable commercial organoclays Cloisite 25A, 10A, and 30B were additionally modified with [3-(glycidyloxy)propyl]trimethoxysilane, hexadecyltrimethoxysilane and (3-aminopropyl)trimethoxysilane. The selected organoclays were compounded in the concentration 5 wt % and their degree of intercalation/delamination was determined by wideangle X-ray scattering and transmission electron microscopy. Modification of Cloisite 25A with [3-(glycidyloxy)-propyl]trimethoxysilane increased homogeneity of silicate layers in recycled PET. Additional modification of Cloisite 10A and Cloisite 30B led to lower level of delamination concomitant with melt viscosity reduction. However, flow characteristics of all studied organoclay nanocomposites showed solid-like behavior at low frequencies. Silanization of commercial organoclays had remarkable impact on crystallinity and melt temperature decrease accompanied by faster formation of crystalline nuclei during injection molding. Thermogravimetric analysis showed enhancement of thermal stability of modified organoclays. The tensile tests confirmed significant increase of PET-R stiffness with organoclays loading and the system containing Cloisite 25A treated with [3-(glycidyloxy)propyl]trimethoxysilane revealed combination of high stiffness and extensibility, which could be utilized for production of high-performance materials by spinning, extrusion, and blow molding technologies.

The Role of Organomodified DifferentLDHson Recycled Poly(ethylene terephthalate) Nanocomposites

“…Finding proper methods of recycling poses a new challenge from the ecological and economic points of view. In particular, only a few studies on recycled PET recovery for the purpose of nanocomposite materials with improved processing and utility properties are found in the literature . Generally, three preparation methods are used for polymer nanocomposites: in situ polymerization, solution mixing, and melt mixing.…”

“…In particular, only a few studies on recycled PET recovery for the purpose of nanocomposite materials with improved processing and utility properties are found in the literature. [14][15][16][17] Generally, three preparation methods are used for polymer nanocomposites: in situ polymerization, solution mixing, and melt mixing. Among the three, melt compounding is the preferred method for the preparation of polymer nanocomposites because of its environmental and economic advantages such as the absence of solvents and monomers.…”

Morphology and mechanical properties of PET/PE blends compatibilized by nanoclays: Effect of thermal stability of nanofiller organic modifier

“…Thus, it would decrease the desired properties of organoclay compatibilized blends. 11 This article reports the preparation of a new thermally stable organosilicate, for compatibilization of immiscible PET/PE blends. Phosphonium 8,[15][16][17] or immidazolium-based surfactants 10,18-23 would be worth being considered for this purpose.…”

“…In the particular case of polymer matrix/organoclay systems, many authors have reported the effect of thermal stability of the clay organomodifier on the dispersion of the organoclay nanoplatelets in the matrix and the resulting mechanical properties. [6][7][8][9][10][11] To our knowledge, no study has addressed the effect of surfactant thermal degradation on the morphology and induced mechanical properties of immiscible polymer blends yet.…”

“…Phosphonium 8,[15][16][17] or immidazolium-based surfactants 10,[18][19][20][21][22][23] would be worth being considered for this purpose. 11 This article reports the preparation of a new thermally stable organosilicate, for compatibilization of immiscible PET/PE blends. For this purpose, an organic modifier surfactant with three phenyl components as functional group and a phosphonium cation was chosen for its ability to satisfy two major conditions: (1) existence of a functional group more compatible with PET matrix than with the PE dispersed phase; (2) existence of a cationic group which is thermally stable at the blend meltmixing temperature (% 270 C).…”