scholarly journals Sustainable Polyurethane Networks Based on Rosin with Reprocessing Performance

Polymers ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 3538
Author(s):  
Jiawei Li ◽  
Weiming Yang ◽  
Zhao Ning ◽  
Bin Yang ◽  
Yanning Zeng
Keyword(s):  
Mechanical Properties ◽  
Mechanical Analysis ◽  
Healing Time ◽  
The Self ◽  
Self Healing ◽  
Hot Press ◽  
Polyurethane Networks ◽  
Network Topologies ◽  
Superior Mechanical Properties ◽  
First Time

Rosin is an abundant natural product. In this paper, for the first time, a rosin derivative is employed as a monomer for the preparation of polyurethane vitrimers with improved properties. A novel rosin-based polyurethane vitrimers network was constructed by the reaction between isocyanates (HDI) as curing agent and monomers with alcohol groups modified from rosin. The dynamic rosin-based polyurethane vitrimers were characterized by FTIR and dynamic mechanical analysis. The obtained rosin-based polyurethane vitrimers possessed superior mechanical properties. Due to the dynamic urethane linkages, the network topologies of rosin-based polyurethane vitrimers could be altered, contributing self-healing and reprocessing abilities. Besides, we investigated the effects of healing time and temperature on the self-healing performance. Moreover, through a hot press, pulverized samples of 70%VPUOH could be reshaped several times, and the mechanical properties of the recycled samples were restored, with tensile strength being even higher than the of that of the original samples.

scholarly journals Rosin-Based Epoxy Vitrimers with Dynamic Boronic Ester Bonds

Polymers ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 3386
Author(s):  
Yanning Zeng ◽  
Jiawei Li ◽  
Shuxin Liu ◽  
Bin Yang
Keyword(s):  
Mechanical Properties ◽  
Mechanical Analysis ◽  
Chemical Degradation ◽  
Self Healing ◽  
Hot Press ◽  
Boronic Ester ◽  
Network Topologies ◽  
Reversible Covalent ◽  
First Time ◽  
Epoxy Groups

Rosin is an abundantly available natural product. In this paper, for the first time, a rosin derivative is employed as the main monomer for preparation of epoxy vitrimers to improve the mechanical properties of vitrimers. Novel epoxy vitrimer networks with dynamic reversible covalent boronic ester bonds are constructed by a reaction between thiols in 2,2′–(1,4–phenylene)–bis (4–mercaptan–1,3,2–dioxaborolane) (BDB) as a curing agent and epoxy groups in the rosin derivative. The rosin-based epoxy vitrimer networks are fully characterized by Fourier transform infrared spectroscopy (FTIR), an equilibrium swelling experiment, and dynamic mechanical analysis (DMA). The obtained rosin-based epoxy vitrimers possess superior thermostability and good mechanical properties. Due to transesterification of boronic ester bonds, rosin epoxy vitrimer network topologies can be altered, giving welding, recycle, self-healing, and shape memory abilities to the fabricated polymer. Besides, the effects of treating time and temperature on welding capability is investigated, and it is found that the welding efficiency of the 20% C-FPAE sample is >93% after treatment for 12 h at 160 °C. Moreover, through a hot press, the pulverized samples of 20% C-FPAE can be reshaped several times and most mechanical properties are restored after reprocessing at 200 °C for 60 min. Finally, chemical degradation is researched for the rosin-based epoxy vitrimers.

scholarly journals Preparation and Mechanical Properties of Microcapsule-Based Self-Healing Cementitious Composites

Materials ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 4866
Author(s):  
Shiping Jiang ◽  
Zhiyang Lin ◽  
Can Tang ◽  
Wenfeng Hao
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Composite Structures ◽  
Healing Time ◽  
The Self ◽  
Self Healing ◽  
Cementitious Composite ◽  
Healing System ◽  
Cement Based Materials ◽  
Curing Agents

Self-healing concrete designs can protect against deterioration and improve durability. However, there is no unified conclusion regarding the effective preparation and mechanical properties of self-healing concrete. In this paper, microcapsules are used in cement-based materials, the reasonable dosage of microcapsules is determined, and the self-healing performance of the microcapsule self-healing system under different curing agents is explored. The microcapsules and curing agent are shown to enhance the flexural and compressive strength of mortar specimens at relatively low contents. The optimal microcapsule content in terms of compressive strength is 1–3%. When the content of the microcapsule reaches 7%, the strength of the specimen decreases by approximately 30%. Sodium fluorosilicate is better-suited to the microcapsule self-healing cement-based system than the other two fluorosilicates, potassium fluorosilicate and magnesium, which have similarly poor healing performance as curing agents. Healing time also appears to significantly influence the microcapsule self-healing system; mortar specimens that healed for 28 days are significantly higher than those that healed for 7 days. This work may provide a valuable reference for the design and preparation of self-healing cementitious composite structures.

scholarly journals The Effect of Superabsorbent Polymers on the Microstructure and Self-Healing Properties of Cementitious-Based Composite Materials

2021 ◽  
Vol 11 (2) ◽  
pp. 700
Author(s):  
Irene A. Kanellopoulou ◽  
Ioannis A. Kartsonakis ◽  
Costas A. Charitidis
Keyword(s):  
Mechanical Properties ◽  
Composite Materials ◽  
Hybrid Structure ◽  
The Self ◽  
Self Healing ◽  
Cementitious Composite ◽  
Superabsorbent Polymers ◽  
Porosity Reduction ◽  
Environment Control ◽  
The Impact

Cementitious structures have prevailed worldwide and are expected to exhibit further growth in the future. Nevertheless, cement cracking is an issue that needs to be addressed in order to enhance structure durability and sustainability especially when exposed to aggressive environments. The purpose of this work was to examine the impact of the Superabsorbent Polymers (SAPs) incorporation into cementitious composite materials (mortars) with respect to their structure (hybrid structure consisting of organic core—inorganic shell) and evaluate the microstructure and self-healing properties of the obtained mortars. The applied SAPs were tailored to maintain their functionality in the cementitious environment. Control and mortar/SAPs specimens with two different SAPs concentrations (1 and 2% bwoc) were molded and their mechanical properties were determined according to EN 196-1, while their microstructure and self-healing behavior were evaluated via microCT. Compressive strength, a key property for mortars, which often degrades with SAPs incorporation, in this work, practically remained intact for all specimens. This is coherent with the porosity reduction and the narrower range of pore size distribution for the mortar/SAPs specimens as determined via microCT. Moreover, the self-healing behavior of mortar-SAPs specimens was enhanced up to 60% compared to control specimens. Conclusively, the overall SAPs functionality in cementitious-based materials was optimized.

scholarly journals Recyclable Self-Healing Polyurethane Cross-Linked by Alkyl Diselenide with Enhanced Mechanical Properties

Polymers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 773 ◽  
Author(s):  
Yuqing Qian ◽  
Xiaowei An ◽  
Xiaofei Huang ◽  
Xiangqiang Pan ◽  
Jian Zhu ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Room Temperature ◽  
Amide Bond ◽  
Self Healing ◽  
Healing Efficiency ◽  
Polyurethane Networks ◽  
Combined Action ◽  
Cross Linker ◽  
Dynamic Structures ◽  
External Interventions

Dynamic structures containing polymers can behave as thermosets at room temperature while maintaining good mechanical properties, showing good reprocessability, repairability, and recyclability. In this work, alkyl diselenide is effectively used as a dynamic cross-linker for the design of self-healing poly(urea–urethane) elastomers, which show quantitative healing efficiency at room temperature, without the need for any catalysts or external interventions. Due to the combined action of the urea bond and amide bond, the material has better mechanical properties. We also compared the self-healing effect of alkyl diselenide-based polyurethanes and alkyl disulfide-based polyurethanes. The alkyl diselenide has been incorporated into polyurethane networks using a para-substituted amine diphenyl alkyl diselenide. The resulting materials not only exhibit faster self-healing properties than the corresponding disulfide-based materials, but also show the ability to be processed at temperatures as low as 60 °C.

Highly Thermoconductive Yet Ultraflexible Polymer Composite with Superior Mechanical Properties and Autonomous Self-Healing Functionality via Binary Fillers Strategy

2022 ◽  
Author(s):  
Dong Wang ◽  
Dingyao Liu ◽  
JianHua Xu ◽  
JiaJun Fu ◽  
Kai Wu
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Polymer Composite ◽  
High Thermal Conductivity ◽  
Thermal Dissipation ◽  
Self Healing ◽  
Formidable Challenge ◽  
Superior Mechanical Properties

It is still a formidable challenge to develop ideal thermal dissipation materials with simultaneous high thermal conductivity, excellent mechanical softness and toughness, and spontaneous self-healing. Herein, we report the introduction...

scholarly journals Nanoparticle-Hydrogel Composites: From Molecular Interactions to Macroscopic Behavior

Polymers ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 275 ◽  
Author(s):  
Corinna Dannert ◽  
Bjørn Torger Stokke ◽  
Rita S. Dias
Keyword(s):  
Mechanical Properties ◽  
Molecular Design ◽  
The Self ◽  
Self Healing ◽  
Sensor Applications ◽  
Composite Gels ◽  
Equilibrium Swelling ◽  
Hydrogel Composites ◽  
Materials Used ◽  
Network Component

Hydrogels are materials used in a variety of applications, ranging from tissue engineering to drug delivery. The incorporation of nanoparticles to yield composite hydrogels has gained substantial momentum over the years since these afford tailor-making and extend material mechanical properties far beyond those achievable through molecular design of the network component. Here, we review different procedures that have been used to integrate nanoparticles into hydrogels; the types of interactions acting between polymers and nanoparticles; and how these underpin the improved mechanical and optical properties of the gels, including the self-healing ability of these composite gels, as well as serving as the basis for future development. In a less explored approach, hydrogels have been used as dispersants of nanomaterials, allowing a larger exposure of the surface of the nanomaterial and thus a better performance in catalytic and sensor applications. Furthermore, the reporting capacity of integrated nanoparticles in hydrogels to assess hydrogel properties, such as equilibrium swelling and elasticity, is highlighted.

MICROSTRUCTURE AND MECHANICAL PROPERTIES OF HYPEREUTECTIC Al-Si/AlNp COMPOSITE

2009 ◽  
Vol 23 (06n07) ◽  
pp. 1377-1382 ◽  
Author(s):  
SEULKI PARK ◽  
JINMYUNG CHOI ◽  
BONGGYU PARK ◽  
IKMIN PARK ◽  
YONGHO PARK ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Energy Dispersive Spectrometer ◽  
Microstructural Characterization ◽  
Weight Fraction ◽  
Reinforcement Particle ◽  
Hot Press ◽  
X Ray Diffraction ◽  
X Ray ◽  
Superior Mechanical Properties ◽  
Phase Evaluation

Hypereutectic Al - Si alloys with fine and evenly distributed Si precipitates have superior mechanical properties In this study, hypereutectic Al - Si alloy powders which contained 15 and 20wt% Si were prepared by a gas atomization process. 1, 3 and 5wt% AlN particles were blended with the Al - Si alloy powders using turbular mixer. The mixture was consolidated by Hot Press at 550°C for 1h under 60MPa. Relative density of the sintered samples was about 98% of theoretical density. This study was investigated by two ways. One is the effect of reinforcement weight fraction and the other is the effect of Silicon contents on the mechanical properties of the composite. Microstructural characterization and phase evaluation were carried out using X-ray Diffraction, Scanning Electron Microscopy equipped with Energy Dispersive Spectrometer. The results showed that the smaller the reinforcement particle size was and the better its distribution was, the higher ultimate tensile strength and hardness were.

scholarly journals Self-Healable Supramolecular Vanadium Pentoxide Reinforced Polydimethylsiloxane-Graft-Polyurethane Composites

Polymers ◽  
2018 ◽  
Vol 11 (1) ◽  
pp. 41 ◽  
Author(s):  
Ali Berkem ◽  
Ahmet Capoglu ◽  
Turgut Nugay ◽  
Erol Sancaktar ◽  
Ilke Anac
Keyword(s):  
Tensile Strength ◽  
Vanadium Pentoxide ◽  
Coupling Reaction ◽  
Optical Microscope ◽  
Mechanical Tests ◽  
Healing Time ◽  
The Self ◽  
Supramolecular Polymer ◽  
Self Healing ◽  
Healing Efficiency

The self-healing ability can be imparted to the polymers by different mechanisms. In this study, self-healing polydimethylsiloxane-graft-polyurethane (PDMS-g-PUR)/Vanadium pentoxide (V2O5) nanofiber supramolecular polymer composites based on a reversible hydrogen bonding mechanism are prepared. V2O5 nanofibers are synthesized via colloidal route and characterized by XRD, SEM, EDX, and TEM techniques. In order to prepare PDMS-g-PUR, linear aliphatic PUR having one –COOH functional group (PUR-COOH) is synthesized and grafted onto aminopropyl functionalized PDMS by EDC/HCl coupling reaction. PUR-COOH and PDMS-g-PUR are characterized by 1H NMR, FTIR. PDMS-g-PUR/V2O5 nanofiber composites are prepared and characterized by DSC/TGA, FTIR, and tensile tests. The self-healing ability of PDMS-graft-PUR and composites are determined by mechanical tests and optical microscope. Tensile strength data obtained from mechanical tests show that healing efficiencies of PDMS-g-PUR increase with healing time and reach 85.4 ± 1.2 % after waiting 120 min at 50 °C. The addition of V2O5 nanofibers enhances the mechanical properties and healing efficiency of the PDMS-g-PUR. An increase of healing efficiency and max tensile strength from 85.4 ± 1.2% to 95.3 ± 0.4% and 113.08 ± 5.24 kPa to 1443.40 ± 8.96 kPa is observed after the addition of 10 wt % V2O5 nanofiber into the polymer.

Study on the Effects of the Self-Healing Microcapsules on the Tensile Properties of Polymer Composite

2011 ◽  
Vol 299-300 ◽  
pp. 460-465 ◽  
Author(s):  
Li Zhang ◽  
Xiu Ping Dong ◽  
Hao Chen
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Elastic Modulus ◽  
Glass Fiber ◽  
Tensile Properties ◽  
Polymer Composite ◽  
Tensile Tests ◽  
The Self ◽  
Self Healing ◽  
Glass Fiber Reinforced

By designing different formulations of composites and adopting optimized technology including extrusion and molding, the different composites with various content microcapsules were prepared. The results of the tensile tests show that with the increasing content of self-healing microcapsules in the glass fiber reinforced nylon composites, the mechanical properties of the composites will change, i.e. tensile strength, elastic modulus will decrease. But there is little effect on the mechanical properties of the composite gears if the content of self-healing microcapsules is less than 3.5%, and the technology of self-healing microcapsules used in the polymer composite gear is feasible.

Sign in / Sign up

Export Citation Format

Share Document