Preparation and characterization of cellulose acetate/polysiloxane composites

Brandão, Larissa Reis; Yoshida, Inez Valéria Pagotto; Felisberti, Maria I.; Gonçalves, Maria do Carmo

doi:10.1007/s10570-013-0039-8

Cited by 15 publications

(8 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The hydrolysis, followed by the selfcondensation reaction of the methoxysilane groups from the siloxanes, promoted the formation of polysilsesquioxane domains, which in turn can act as cross-linking centers in the It is well-known that the morphology of cast films depends on several factors, such as composition, rate of solvent/ dispersant removal, and solution/suspension viscosity. 29,30 In this sense, the morphological characteristics of the herein produced films were elucidated by SEM and AFM (Figure 1). The surface of the BCNC-GPTMS film was inhomogeneous, as evidenced by small aggregates that suggest that the siloxane was not totally incorporated onto the BCNC surface.…”

Section: Resultssupporting

confidence: 61%

Fabrication of Noncytotoxic Functional Siloxane-Coated Bacterial Cellulose Nanocrystals

Lima

Conte

Brandão

et al. 2022

ACS Appl. Polym. Mater.

View full text Add to dashboard Cite

Bacterial cellulose nanocrystals (BCNC) stand out as versatile biocolloidal building blocks for materials that are highperformance, owing to their inherently high crystallinity and specific modulus and surface area, and sustainable, as BCNC are both biobased and biodegradable. BCNC materials are also promising for their multifunctionality because of their huge potential to undergo physical and/or chemical surface modification. This is particularly appealing for biomedical applications thanks to the biocompatibility, high purity, and low toxicity of BCNC. We report on films based on surface-modified BCNC with varying contents of 3-glycidyloxypropyltrimethoxysilane (GPTMS) or 3-aminopropyltriethoxysilane (APTS). Importantly, these highly pure and crystalline needle-shaped BCNC were isolated from scraps generated at industrial operations when shaping bacterial cellulose membranes into wound dressings. The films were extensively characterized as far as their structural characteristics, with emphasis on the major features targeting at biological applications. Compared with pristine BCNC, the films performed better from the thermal stability standpoint and maintained the noncytotoxicity against nontransforming fibroblasts. The latter claim was independent of GPTMS content, but dose-dependent for APTS and valid for films containing up to 30% of this coupling agent. Altogether, this contribution expands the wingspan of nanocellulose-based materials in biomedical applications while mitigating the waste of natural resources by upcycling an industrial byproduct, falling within the circular bioeconomy framework.

show abstract

Section: Resultssupporting

confidence: 61%

Fabrication of Noncytotoxic Functional Siloxane-Coated Bacterial Cellulose Nanocrystals

Lima

Conte

Brandão

et al. 2022

ACS Appl. Polym. Mater.

View full text Add to dashboard Cite

show abstract

“…For CA/TEC and composite samples, these two events can also correspond to the loss of TEC plasticizer. The last weight loss region, from 350 to 425 °C, is referred to as the thermal degradation of the cellulose main chain . These results show that irrespective of the CNC addition method, no pronounced changes in the thermal degradation behavior are observed for the composites prepared.…”

Section: Resultsmentioning

confidence: 93%

Morphological investigation of cellulose acetate/cellulose nanocrystal composites obtained by melt extrusion

Leite

Battirola

Silva

et al. 2016

J of Applied Polymer Sci

Self Cite

View full text Add to dashboard Cite

Composites were prepared from cellulose acetate (CA) and cellulose nanocrystals (CNC) by melt extrusion using two methods for the introduction of CNC: direct mixing and predispersion in CA solution. CNC were isolated using hydrochloric acid to increase thermal stability allowing the composites to be processed above 150 °C. The effect of CNC dispersion on the composites morphology, thermal, and mechanical properties was investigated. Field emission scanning electron microscopy and transmission electron microscopy results indicated that the predispersion method allows better CNC dispersion and distribution when compared to the direct mixture method. In addition, predispersion promotes preferential CNC orientation in relation to the injection flow. The predispersion method also showed a 14% Young's modulus increase in composites containing 15 wt % CNC while no significant change was observed when using the direct mixing. The results obtained in this work show that, to achieve the percolation threshold, nanoparticle distribution is as important as their content. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44201.

show abstract

“…It is observed that the cross-sectional morphology of the CA/Al 2 O 3 nanocomposite exhibits a three-dimensional ordered porous structure with better orientation. Such a porous structure could be attributed to the microphase separation in a CA/Al 2 O 3 /acetone/water mixture. , Also, a magnified view in Figure e clearly shows that the pore skeleton is rough and is shaped like little waves. The surface morphology of the CA/Al 2 O 3 nanocomposite was also examined, as shown in Figure f.…”

Section: Resultsmentioning

confidence: 94%

“…Such a porous structure could be attributed to the microphase separation in a CA/Al 2 O 3 /acetone/water mixture. 25,26 Also, a magnified view in Figure 1e clearly shows that the pore skeleton is rough and is shaped like little waves. The surface morphology of the CA/Al 2 O 3 nanocomposite was also examined, as shown in Figure 1f.…”

Section: ■ Results and Discussionmentioning

confidence: 98%

An Eco-friendly Porous Nanocomposite Fabric-Based Triboelectric Nanogenerator for Efficient Energy Harvesting and Motion Sensing

Bai

et al. 2020

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

A wearable and effective tribopositive material, especially an economical and eco-friendly triboelectric fabric developed from biomaterials, is highly crucial for the development of green wearable triboelectric nanogenerators. In this work, we design a porous nanocomposite fabric (PNF) with strong charge accumulation capacity through a facile dry-casting method and use it as a tribopositive material to construct attractive wearable triboelectric nanogenerators (abbreviated as TENGs). Specifically, the porous nanocomposite is developed by the incorporation of nano-Al 2 O 3 fillers into cellulose acetate networks. By adjusting the concentration of casting solution and the content of nano-Al 2 O 3 fillers, we systematically engineer the physical properties of the PNF for obtaining a large triboelectric charge yield. When a 10 wt % solution concentration and 10 wt % nanofiller content are adopted for the PNF, the corresponding PNF-TENG can deliver an electrical performance of ∼2.5 mW/cm 2 on a 0.8 MΩ external resistor. This remarkable output can be ascribed to the synergistic effect between the appropriate porous network and improved dielectric properties of the nanocomposite. Moreover, the PNF-TENG also exhibits good reliable electrical outputs under multiple stain-washing measurements or after experiencing cyclical contact− separation 13,500 times. Also, the device is capable of charging various capacitors, lighting LED arrays, and driving commercial wrist watches and is proven to be an efficient and reliable green wearable power source. Furthermore, a PNF-TENG-based elbow supporter and a grip ball, as self-powered sensors, are proposed to realize real-time detection for human actions during sports exercise. This work proposes an eco-friendly nanocomposite fabric as an effective tribopositive material, verifies the feasibility of developing environmentally friendly wearable power sources and sensors, and provides new insights into the design of green wearable triboelectric nanogenerators.

show abstract

Preparation and characterization of cellulose acetate/polysiloxane composites

Cited by 15 publications

References 33 publications

Fabrication of Noncytotoxic Functional Siloxane-Coated Bacterial Cellulose Nanocrystals

Fabrication of Noncytotoxic Functional Siloxane-Coated Bacterial Cellulose Nanocrystals

Morphological investigation of cellulose acetate/cellulose nanocrystal composites obtained by melt extrusion

An Eco-friendly Porous Nanocomposite Fabric-Based Triboelectric Nanogenerator for Efficient Energy Harvesting and Motion Sensing

Contact Info

Product

Resources

About