Impact of starch nanocrystals on the physicochemical, thermal and structural characteristics of starch-based films

Latorres

Polymer Engineering & Sci

et al. 2022

Self Cite

The aim of this study is to add rice and potato starch nanocrystals (SNCs) to a low-density polyethylene (LDPE) matrix to reinforce its structure, improve its characteristics, and broaden its applicability. The SNCs were produced by acid hydrolysis and applied to the LDPE matrix by extrusion at a concentration of 0.5% and 1%. The films were characterized in terms of physical-chemical, thermal, and structural properties. The addition of 1% SNCs produced from rice starch reduced the oxygen permeability to 1.57 Â 10 À4 (ml mm/MPa/ min/cm 2 ) and increased the thermal stability of the films. The addition of potato starch SNCs in a 1% proportion increased the crystallinity of the films to 81.6%. Therefore, the incorporation of starch SNCs in the LDPE matrix showed adequate compatibility and the ability to improve the properties of the films. The mixture of LDPE with biodegradable polymers can be an alternative that can contribute to the increase in the rate of biodegradability.

Section: Resultsmentioning

confidence: 99%

Effect of starch nanocrystals addition on the physicochemical, thermal, and optical properties of low‐density polyethylene (LDPE) films

Latorres

Polymer Engineering & Sci

et al. 2022

Self Cite

“…The nanocrystals used as structural reinforcement of the PLA films developed in this study were previously elaborated and extensively characterized according to the study of Martins, Latorres, and Martins. 23 More details about structural and thermal characterizations are presented in Figure 1-3. The micrographs of native starches and SNCs are shown in Figure 1a-d.…”

Section: Characterization Of Sncsmentioning

confidence: 99%

Enhancement of polylactic acid films properties by incorporation of starch nanocrystals

J of Applied Polymer Sci

Latorres

Machado

et al. 2022

Self Cite

Polylactic acid (PLA) is a biodegradable polymer used in films production; however, it has some limitations. Thus, strategies can be used to improve the characteristics of these materials such as the incorporation of starch nanocrystals (SNCs). Therefore, the aim of this study was to add potato and rice SNCs in PLA matrix in the melt to obtain PLA films with structural reinforcement to improve its properties. The SNCs were produced by acid hydrolysis and incorporated to the matrix in 0.5 and 1 wt% amounts. The films were then produced by bioriented tubular extrusion and characterized with several techniques. Films containing 1 wt% of potato SNCs showed an increase in tensile strength, elongation, and glass transition temperature, but a reduction in water vapor permeability. Therefore, the use of potato SNCs as a structural reinforcement for PLA films improved the properties of the films making them suitable candidates for several other applications.

“…Zhang H et al [ 15 ] increased pea starch films’ tensile strength and relative crystallinity by acid hydrolysis of pea starch with hydrochloric acid. In the study by Martins et al [ 16 ], films were prepared from acid-hydrolyzed (hydrochloric acid) and esterified rice starch (citric acid), which exhibited higher tensile strength and relative crystallinity and better biodegradability, but lower water solubility. Although starch is not thermoplastic, it can be extruded or injected to produce films, similar to other polymers, after the addition or in the presence of plasticizers such as glycerol or water [ 17 ].…”

Section: Introductionmentioning

confidence: 99%

Accelerated Shelf-Life and Stability Testing of Hydrolyzed Corn Starch Films

et al. 2023

Nonbiodegradable food packaging films are made from plastics such as polyethylene and polypropylene, which can take hundreds of years to decompose and create environmental hazards. On the other hand, biodegradable food packaging films are made from renewable materials such as corn starch or cellulose, that degrade within a few weeks or months and prove to be more sustainable and environmentally friendly. In this work, we used corn starch hydrolyzed (CSH) with α-amylase to prepare a film with biodegradable properties. The film was tested for 60 days at different accelerated temperatures and relative humidity (RH), 13 ± 2 °C and 65 ± 5% RH, 23 ± 2 °C and 45 ± 5% RH, and 33 ± 2 °C and 30 ± 5% RH, to test its durability and stability. Soil biodegradation of the CSH film was evaluated by visual appearance, microscopic observation, weight loss, scanning electron microscopy (SEM), and Fourier-transformed infrared spectroscopy (FTIR) every 6 days. The film was found to have strong hygroscopic properties and was able to last up to 10 months if it is maintained at 20 ± 5 °C and 45 ± 5% RH. After the biodegradability test for at least 30 days, the film showed a significantly higher weight loss rate and microbial activity on the surface of the film, which indicates that the film is biodegradable. The present work recommends biodegradable CSH films as an excellent environmentally friendly choice for dried foods packaging, due to their good shelf life at room temperature, which is beneficial when shipping and storing products, but these films are not suitable for foods with high moisture content.