Premium
Biodegradable PLA based nanocomposites for packaging applications: The effects of organo‐modified bentonite concentration
Author(s) -
Bezerra Lima Edla Maria,
Middea Antonieta,
Marconcini José Manoel,
Corrêa Ana Carolina,
Fernandes Pereira Jéssica,
Vieira Guimarães Alessandra,
Firmino de Lima Josimar,
Ramos dos Anjos Marianna,
Miranda de Castro Izabela,
Nunes Oliveira Renata,
Ramos Moreira Carla,
Paiva Maurício Magalhães,
Rangel Francisco Luiz Correa,
Neumann Reiner
Publication year - 2021
Publication title -
journal of applied polymer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.575
H-Index - 166
eISSN - 1097-4628
pISSN - 0021-8995
DOI - 10.1002/app.50907
Subject(s) - organoclay , materials science , crystallinity , nanocomposite , bentonite , polylactic acid , crystallization , chemical engineering , composite material , polymer , engineering
The effects of concentration and surface modification of two Brazilian bentonite clays on nanocomposites' properties based on polylactic acid – (PLA) were investigated. The samples were prepared by the extrusion/injection method to obtain biodegradable packaging plastics. The raw materials and their bionanocomposites were characterized by various techniques. Natural clay samples presented a size of around 2 μm while the modified ones' size was 5–6 μm, probably due to the presence of cetyltrimethylammonium bromide in the interlayer space. The particle size and the contact angle increased with the treatment and the clay's density decreased. The organoclays were homogeneously dispersed in PLA, which can be associated with the interactions between PLA chains' carbonyl groups and the organoclays. The bionanocomposites present modified clay particles axis aligned to the flow direction of the extruder/injector. Chocolate organoclay acts as a nucleating agent to PLA crystal growth, increasing the sample's crystallinity, while Bofe organoclay interferes with the amorphous chain's mobility and diminishes the sample's crystallization. The addition of both organoclays to PLA diminished the sample's elongation at break and strength, although the organoclays increased the sample's Young modulus, even though Bofe organoclay is more active in PLA amorphous phase and Chocolate organoclay on the crystalline one.