Plasticisation of carnauba wax with generally recognised as safe (GRAS) additives

Zhang, Yan; Adams, M.J.; Zhang, Zhibing; Vidoni, Olivia; Leuenberger, Bruno; Achkar, Jihane

doi:10.1016/j.polymer.2016.01.033

Cited by 12 publications

(4 citation statements)

References 28 publications

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“…This is in line with previous results showing methyl oleate induced loss of crystallinity in tristearin, serving as a model for cuticular wax . Moreover, nonionic surfactant adjuvants like ethoxylated polysorbates have been shown to decrease crystallinity in carnauba wax, which implies that the monodisperse alcohol ethoxylate C12E2 used in our study had similar effects on the crystallinity of the paraffin. Ongoing work in the authors’ lab is currently investigating the impact of adjuvant-induced changes in the structural properties of the wax, such as the decrease in orthorhombic crystallinity, which using ATR-FTIR can be detected simultaneously during a diffusion experiment.…”

Section: Discussionsupporting

confidence: 93%

Diffusion Kinetics of Active Ingredients and Adjuvants in Wax Films: An Attenuated Total Reflection-Infrared Spectroscopy Study of a Leaf Surface Model

Kunz

Staiger

Burghardt

et al. 2022

ACS Agric. Sci. Technol.

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The penetration of the wax barrier of plant cuticles is the rate-limiting step for the uptake of surface applied pesticides. Optimizing the uptake rates of active ingredients across this barrier is a significant objective of the rational design of pesticide formulations. We used an ATR-FTIR-based method for determining the diffusion coefficients derived from Fickian diffusion kinetics in paraffin wax of model diffusants differing in chemical structure, lipophilicity, and size at different temperatures. At 25 °C, the diffusion coefficients of 4-cyanophenol and heptyl parabene were 1.48 × 10–15 and 1.73 × 10–15 m2 s–1, respectively, and increased from 25 to 40 °C yielding activation energies of 54 kJ mol–1 and 71 kJ mol–1, respectively. In contrast, much higher diffusion coefficients were obtained for the accelerating adjuvants methyl oleate (1.49 × 10–13 m2 s–1) and C12E2 (4.52 × 10–14 m2 s–1), exhibiting entirely Fickian diffusion kinetics. The diffusion coefficients in wax are 3–5 orders of magnitude lower than diffusion coefficients in water predicted for these molecules, which illustrates the massive barrier the cuticle forms against the uptake of solutes. The current work demonstrates ATR-FTIR’s suitability as a new approach to optimizing pesticide formulations by quantitatively investigating active ingredient and adjuvant mobility in thin wax films.

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Section: Discussionsupporting

confidence: 93%

Diffusion Kinetics of Active Ingredients and Adjuvants in Wax Films: An Attenuated Total Reflection-Infrared Spectroscopy Study of a Leaf Surface Model

Kunz

Staiger

Burghardt

et al. 2022

ACS Agric. Sci. Technol.

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“…Some of these have lower melting temperature than others. The overall melting temperature for carnauba wax in literature ranges around 84 °C, with values reported between 82 °C and 86 °C (Bayer et al, 2011;Shellhammer, Rumsey, & Krochta, 1997;Zhang et al, 2016). Despite this, some components start melting already at lower temperatures, indicated by reported melting ranges as broad as 65-90 °C (Basson & Reynhardt, 1988).…”

Section: The Effect Of Curing Temperature On Hydrophobicity Of Coatedmentioning

confidence: 98%

“…There are two possible reasons for this phenomenon. Carnauba wax is a natural material and consists of different molecules, mostly wax esters, some free fatty alcohols and free fatty acids (Basson & Reynhardt, 1988;Doan et al, 2017;Zhang et al, 2016). Some of these have lower melting temperature than others.…”

Section: The Effect Of Curing Temperature On Hydrophobicity Of Coatedmentioning

confidence: 99%

Open coating with natural wax particles enables scalable, non-toxic hydrophobation of cellulose-based textiles

Forsman

Johansson

Koivula

et al. 2020

Carbohydrate Polymers

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This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

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“…The result can be a plasticizing effect, including a reduction of film strength and an increase in film flexibility [ 8 , 9 ]. Polymer plasticization is the disruption of polymer-polymer interactions and the replacement with plasticizer-polymer interactions increasing the free volume within the polymer structure, allowing more movement of the chains and hence increasing flexibility [ 10 ]. It is reasonable that the plasticizing agent used in the mixture with biopolymers is preferably biodegradable, for example, natural waxes.…”

Section: Introductionmentioning

confidence: 99%

Effect of the Addition of Different Natural Waxes on the Mechanical and Rheological Behavior of PLA—A Comparative Study

et al. 2023

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In this study, poly(lactic acid) (PLA) blended with different natural waxes (beeswax, candelilla, carnauba, and cocoa) was investigated. Different wax amounts, 3, 5, 10, and 15 wt%, were incorporated into the PLA using a Brabender internal mixer. The blends were characterized by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), rotational rheometer (RR), dynamic mechanical analysis (DMA), and contact angle to observe the effect of the different waxes on the PLA physicochemical, rheological, mechanical behavior, and wetting properties. The complex viscosity of the blends was studied by employing a RR. The effect of the addition of the waxes on the mechanical properties of PLA was evaluated by DMA in the tension modality. A slight decrease in the thermal stability of PLA was observed with the addition of the waxes. However, in the case of the mechanical properties, the cocoa wax showed a considerable effect, especially in the elongation at break of PLA. Likewise, waxes had an essential impact on the water affinity of PLA. Specifically, with the addition of cocoa, the PLA became more hydrophilic, while the rest of the waxes increased the hydrophobic character.

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Plasticisation of carnauba wax with generally recognised as safe (GRAS) additives

Cited by 12 publications

References 28 publications

Diffusion Kinetics of Active Ingredients and Adjuvants in Wax Films: An Attenuated Total Reflection-Infrared Spectroscopy Study of a Leaf Surface Model

Diffusion Kinetics of Active Ingredients and Adjuvants in Wax Films: An Attenuated Total Reflection-Infrared Spectroscopy Study of a Leaf Surface Model

Open coating with natural wax particles enables scalable, non-toxic hydrophobation of cellulose-based textiles

Effect of the Addition of Different Natural Waxes on the Mechanical and Rheological Behavior of PLA—A Comparative Study

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