Cellulose nanofibers/polyurethane shape memory composites with fast water-responsivity

In this study, a series of heat-induced shape memory composites was prepared by the hot-melt extrusion and three-dimensional (3D) printing of thermoplastic polyurethane (TPU) using wood flour (WF) with different contents of EPDM-g-MAH. The mechanical properties, microtopography, thermal property analysis, and heat-induced shape memory properties of the composites were examined. The results showed that, when the EPDM-g-MAH content was 4%, the tensile elongation and tensile strength of the composites reached the maximum value. The scanning electron microscopy and dynamic mechanical analysis results revealed a good interface bonding between TPU and WF when the EPDM-g-MAH content was 4%. The thermogravimetric analysis indicated that the thermal stability of TPU/WF composites was enhanced by the addition of 4% EPDM-g-MAH. Heat-induced shape memory test results showed that the shape memory performance of composites with 4% EPDM-g-MAH was better than that of unmodified-composites. The composites’ shape recovery performance at a temperature of 60 °C was higher than that of the composites at ambient temperature. It was also found that, when the filling angle of the specimen was 45°, the recovery angle of the composites was larger.

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An investigation on electro-induced shape memory performances of CE/EP/CB/SCF composites applied for deployable structure

Journal of Polymer Engineering ◽

10.1515/polyeng-2019-0212 ◽

2020 ◽

Vol 40 (3) ◽

pp. 203-210 ◽

Cited By ~ 1

Author(s):

Tianning Ren ◽

Guangming Zhu ◽

Yi Liu ◽

Xiao Hou

Keyword(s):

Carbon Black ◽

Shape Memory ◽

Memory Performance ◽

Shape Memory Polymer ◽

Content Increase ◽

Deployable Structure ◽

Shape Memory Properties ◽

Shape Memory Composites ◽

Shape Memory Composite ◽

Short Carbon

AbstractThe objective of this work is to investigate the thermomechanical, electrical, and shape-memory properties of bisphenol A-type cyanate ester (BACE)/polybutadiene epoxy (PBEP)/carbon black (CB) composite and assess its feasibility applied for deployable structure. Using a BACE/PBEP polymer as matrix and superconducting carbon black (CB) and short carbon fibers (SCFs) as reinforcing material, the shape memory composite was prepared by compression molding. The effects of CB and SCF content on the shape memory properties of the composites were investigated. The results demonstrate that the glass transition temperature (Tg) and the storage modulus of the composites increases as SCFs content increase. Because of the synergic effect of CB and SCFs, the shape memory composites exhibit excellent shape memory performance, and the shape recovery ratio is about 100%. With the increase in SCF content, the recovery time decreased, and the volume electrical resistivity of the composite could decrease by adding a small amount of SCFs. According to the above results, a shape memory polymer composite deployable structure was prepared.

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Facile Fabrication of Eucommia Rubber Composites with High Shape Memory Performance

Polymers ◽

10.3390/polym13203479 ◽

2021 ◽

Vol 13 (20) ◽

pp. 3479

Author(s):

Lin Xia ◽

Jiafeng Meng ◽

Yuan Ma ◽

Ping Zhao

Keyword(s):

Mechanical Properties ◽

Shape Memory ◽

Memory Performance ◽

Analytical Techniques ◽

Cross Linking ◽

Rubber Composites ◽

Restoring Force ◽

Shape Memory Composites ◽

Facile Fabrication ◽

Properties Of Materials

We processed a series of shape memory Eucommia rubber (ER) composites with both carbon–carbon and ionic cross-linking networks via a chemical cross-linking method. The influence of the carbon–carbon cross-linking and ion cross-linking degree of ER composites on curing, mechanical, thermal, and shape memory properties were studied by DSC, DMA, and other analytical techniques. Dicumyl peroxide (DCP) and zinc dimethacrylate (ZDMA) played a key role in preparing ER composites with a double cross-linking structure, where DCP initiated polymerization of ZDMA, and grafted ZDMA onto polymer molecular chains and cross-linked rubber molecular chains. Meanwhile, ZDMA combined with rubber macromolecules to build ionic cross-linking bonds in composites under the action of DCP and reinforced the ER composites. The result showed that the coexistence of these two cross-linking networks provide a sufficient restoring force for deformation of shape memory composites. The addition of ZDMA not only improved the mechanical properties of materials, but also significantly enhanced shape memory performance of composites. In particular, Eucommia rubber composites exhibited outstanding mechanical properties and shape memory performance when DCP content was 0.2 phr.

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Swelling Resistance and Water-Induced Shape Memory Performances of Sisal Cellulose Nanofibers/Polyethylene Glycol/Citric Acid Nanocellulose Papers

Journal of Nanomaterials ◽

10.1155/2019/4304532 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9

Author(s):

Zuocai Zhang ◽

Yuqi Li ◽

Laifu Song ◽

Li Ren ◽

Xu Xu ◽

...

Keyword(s):

Polyethylene Glycol ◽

Citric Acid ◽

Shape Memory ◽

Self Assembly ◽

Memory Performance ◽

Cellulose Nanofibers ◽

Tensile Modulus ◽

Response Speed ◽

Shape Memory Materials ◽

Water Swelling

In this work, a kind of nanocomposite paper was obtained by evaporation-induced self-assembly of a mixture of sisal cellulose nanofibers (CNF) and polyethylene glycol (PEG) as the matrix and citric acid (CA) as a cross-linking agent. The CNF/PEG/CA paper exhibited good water swelling resistance which could be controlled by changing the concentration of CA. In addition, this nanocomposite paper exhibited good mechanical properties and water-induced shape memory performance. In particular, when the dosage of CA was 30 wt.%, the tensile strength and the tensile modulus of the CNF/PEG/CA paper after swelling were 25.2 MPa and 813.0 MPa, respectively. Further, this nanocomposite showed great potential for water-induced shape memory materials with fast response speed. The shape recovery rate (Rr) of the CNF/PEG/CA paper reached 90.2% with 30 wt.% CA after being immersed in water for 11 s. It is anticipated that our current work can be used to exploit more efficient methods to overcome the poor water swelling resistance of the cellulose-based shape memory materials.

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Actuation of shape memory polymer composites triggered by electrical resistive heating

Journal of Intelligent Material Systems and Structures ◽

10.1177/1045389x17689944 ◽

2017 ◽

Vol 28 (17) ◽

pp. 2363-2371 ◽

Cited By ~ 2

Author(s):

M Sendil Murugan ◽

Sandhya Rao ◽

MC Chiranjeevi ◽

A Revathi ◽

Kavitha V Rao ◽

...

Keyword(s):

Shape Memory ◽

Polymer Composites ◽

Memory Performance ◽

Shape Memory Polymer ◽

Point Of View ◽

Electrical Actuation ◽

Thermal Actuation ◽

Shape Memory Composites ◽

Shape Memory Behaviour ◽

Set Up

A shape memory polymer is capable of multifunctional performance, be it structural or non-structural. Several actuation mechanisms can be employed to trigger shape memory behaviour. Among these, thermal actuation is most comprehensively studied and applied due to its ease of understanding and utility. However, from the point of view of some niche applications, electrical actuation also needs to be examined. This is all the more relevant for modern aircraft where actuation is amenable to remote computer controls and advanced instrumentation. This in turn paves the way for realizing lightweight and adaptive aircraft structures. In this work, shape memory performance via electrical actuation of unidirectional carbon ply–epoxy shape memory polymer composites has been investigated using an in-house designed test set-up in the manual and automated modes. The synergistic role of carbon plies and the epoxy shape memory polymer matrix for realizing faster shape recovery has been observed. The effect of number of carbon plies on the cyclic shape memory performance of the shape memory polymer composite has also been evaluated. This work demonstrates the feasibility of developing efficient electrically actuated shape memory composites and their potential for different applications.

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Effect of Carbon Nanotubes on the Shape Memory Performance of Poly(vinylidene fluoride)/Acrylic Blends

ACTA AGRONOMICA SINICA ◽

10.3724/sp.j.1095.2012.20104 ◽

2013 ◽

Vol 30 (2) ◽

pp. 134

Author(s):

Hui FU ◽

Jishan QIU ◽

Ning CHONG ◽

Yaqing WANG ◽

Yuanyuan TIAN ◽

...

Keyword(s):

Carbon Nanotubes ◽

Shape Memory ◽

Vinylidene Fluoride ◽

Memory Performance ◽

Poly Vinylidene Fluoride

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NIR-II light-responsive biodegradable shape memory composites based on cuprorivaite nanosheets for enhanced tissue reconstruction

Chemical Engineering Journal ◽

10.1016/j.cej.2021.129437 ◽

2021 ◽

Vol 419 ◽

pp. 129437

Author(s):

Chen Yang ◽

Rui Zheng ◽

Muhammad Rizwan Younis ◽

Jundong Shao ◽

Lian-Hua Fu ◽

...

Keyword(s):

Shape Memory ◽

Shape Memory Composites ◽

Tissue Reconstruction

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In Situ Generation of Green Hybrid Nanofibrillar Polymer-Polymer Composites—A Novel Approach to the Triple Shape Memory Polymer Formation

Polymers ◽

10.3390/polym13121900 ◽

2021 ◽

Vol 13 (12) ◽

pp. 1900

Author(s):

Ramin Hosseinnezhad ◽

Iurii Vozniak ◽

Fahmi Zaïri

Keyword(s):

Polymer Blends ◽

Shape Memory ◽

Shape Memory Polymer ◽

Cellulose Nanofibers ◽

Polymeric Materials ◽

Novel Approach ◽

Phase Transition Temperatures ◽

Triple Shape Memory

The paper discusses the possibility of using in situ generated hybrid polymer-polymer nanocomposites as polymeric materials with triple shape memory, which, unlike conventional polymer blends with triple shape memory, are characterized by fully separated phase transition temperatures and strongest bonding between the polymer blends phase interfaces which are critical to the shape fixing and recovery. This was demonstrated using the three-component system polylactide/polybutylene adipateterephthalate/cellulose nanofibers (PLA/PBAT/CNFs). The role of in situ generated PBAT nanofibers and CNFs in the formation of efficient physical crosslinks at PLA-PBAT, PLA-CNF and PBAT-CNF interfaces and the effect of CNFs on the PBAT fibrillation and crystallization processes were elucidated. The in situ generated composites showed drastically higher values of strain recovery ratios, strain fixity ratios, faster recovery rate and better mechanical properties compared to the blend.

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