Clay intercalation and influence on crystallinity of EVA-based clay nanocomposites

In situanionic homo- and copolymerization of caprolactam (CL) and laurolactam (LL) with sodium montmorillonite clay (NaMMT) was carried out using two different initiators, sodium caprolactamate (CLNa) and caprolactam magnesium bromide (CLMgBr). Degree of conversion and final molecular weight were used to assess the advancement and efficiency of the polymerization reaction and X-ray diffraction and electron microscopy were used to evaluate the sodium montmorillonite clay intercalation/exfoliation. The use of CLNa as initiator produced a higher conversion degree and molecular weight than the use of CLMgBr. Through DSC, it was observed that CLNa and CLMgBr tended to produce random and block copolymer structures, respectively, and either random or block, this eventually has an effect on the clay dispersion within the polymer matrix. In all cases, increasing the LL content produced a decrease in the conversion degree and in the molecular weight of the resulting polymer.

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Hydrogel-clay Nanocomposites as Carriers for Controlled Release

Current Medicinal Chemistry ◽

10.2174/0929867325666180831151055 ◽

2020 ◽

Vol 27 (6) ◽

pp. 919-954 ◽

Cited By ~ 4

Author(s):

Raluca Ianchis ◽

Claudia Mihaela Ninciuleanu ◽

Ioana Catalina Gifu ◽

Elvira Alexandrescu ◽

Cristina Lavinia Nistor ◽

...

Keyword(s):

Drug Delivery ◽

Controlled Release ◽

Hybrid Materials ◽

Pharmaceutical Formulations ◽

Tree Of Life ◽

Present Review ◽

Clay Nanocomposites ◽

Delivery Platform ◽

Complex Hybrid

The present review aims to summarize the research efforts undertaken in the last few years in the development and testing of hydrogel-clay nanocomposites proposed as carriers for controlled release of diverse drugs. Their advantages, disadvantages and different compositions of polymers/biopolymers with diverse types of clays, as well as their interactions are discussed. Illustrative examples of studies regarding hydrogel-clay nanocomposites are detailed in order to underline the progressive researches on hydrogel-clay-drug pharmaceutical formulations able to respond to a series of demands for the most diverse applications. Brief descriptions of the different techniques used for the characterization of the obtained complex hybrid materials such as: swelling, TGA, DSC, FTIR, XRD, mechanical, SEM, TEM and biology tests, are also included. Enlightened by the presented data, we can suppose that hydrogel-clay nanocomposites will still be a challenging subject of global assiduous researches. We can dare to dream to an efficient drug delivery platform for the treatment of multiple affection concomitantly, these being undoubtedly like ”a tree of life” bearing different kinds of fruits and leaves proper for human healing.

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The Roles of Process Parameters on Structures and Mechanical Properties of Polypropylene/Clay Nanocomposites

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/553/1/012044 ◽

2019 ◽

Vol 553 ◽

pp. 012044

Author(s):

Annisa Rifathin ◽

Onny Ujianto ◽

Nurul Jamilah ◽

Afrinaldi Bambang

Keyword(s):

Mechanical Properties ◽

Process Parameters ◽

Clay Nanocomposites

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Probing polymer chain constraint and synergistic effects in nylon 6-clay nanocomposites and nylon 6-silica flake sub-micro composites with nanomechanics

Nanocomposites ◽

10.1080/20550324.2015.1116842 ◽

2015 ◽

Vol 1 (4) ◽

pp. 185-194 ◽

Cited By ~ 2

Author(s):

Jian Chen ◽

Ben D. Beake ◽

Gerard A. Bell ◽

Yalan Tait ◽

Fengge Gao

Keyword(s):

Polymer Chain ◽

Synergistic Effects ◽

Nylon 6 ◽

Clay Nanocomposites

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Effect of Organic Modifier Types on the Physical–Mechanical Properties and Overall Migration of Post-Consumer Polypropylene/Clay Nanocomposites for Food Packaging

Polymers ◽

10.3390/polym13091502 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1502

Author(s):

Eliezer Velásquez ◽

Sebastián Espinoza ◽

Ximena Valenzuela ◽

Luan Garrido ◽

María José Galotto ◽

...

Keyword(s):

Mechanical Properties ◽

Food Packaging ◽

Clay Nanocomposites ◽

Organic Modifier ◽

Thermal And Mechanical Properties ◽

Chemical Safety ◽

Elongation At Break ◽

Fatty Food ◽

Recycled Plastics ◽

Thermal Stability Of

The deterioration of the physical–mechanical properties and loss of the chemical safety of plastics after consumption are topics of concern for food packaging applications. Incorporating nanoclays is an alternative to improve the performance of recycled plastics. However, properties and overall migration from polymer/clay nanocomposites to food require to be evaluated case-by-case. This work aimed to investigate the effect of organic modifier types of clays on the structural, thermal and mechanical properties and the overall migration of nanocomposites based on 50/50 virgin and recycled post-consumer polypropylene blend (VPP/RPP) and organoclays for food packaging applications. The clay with the most hydrophobic organic modifier caused higher thermal stability of the nanocomposites and greater intercalation of polypropylene between clay mineral layers but increased the overall migration to a fatty food simulant. This migration value was higher from the 50/50 VPP/RPP film than from VPP. Nonetheless, clays reduced the migration and even more when the clay had greater hydrophilicity because of lower interactions between the nanocomposite and the fatty simulant. Conversely, nanocomposites and VPP/RPP control films exhibited low migration values in the acid and non-acid food simulants. Regarding tensile parameters, elongation at break values of PP film significantly increased with RPP addition, but the incorporation of organoclays reduced its ductility to values closer to the VPP.

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