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13 pages, 3511 KiB

Open AccessArticle

Linear Capacitive Pressure Sensor with Gradient Architecture through Laser Ablation on MWCNT/Ecoflex Film

by Chenkai Jiang and Bin Sheng

Polymers 2024, 16(7), 962; https://doi.org/10.3390/polym16070962 - 2 Apr 2024

Cited by 2 | Viewed by 1434

Abstract

The practical application of flexible pressure sensors, including electronic skins, wearable devices, human–machine interaction, etc., has attracted widespread attention. However, the linear response range of pressure sensors remains an issue. Ecoflex, as a silicone rubber, is a common material for flexible pressure sensors. [...] Read more.

The practical application of flexible pressure sensors, including electronic skins, wearable devices, human–machine interaction, etc., has attracted widespread attention. However, the linear response range of pressure sensors remains an issue. Ecoflex, as a silicone rubber, is a common material for flexible pressure sensors. Herein, we have innovatively designed and fabricated a pressure sensor with a gradient micro-cone architecture generated by CO₂ laser ablation of MWCNT/Ecoflex dielectric layer film. In cooperation with the gradient micro-cone architecture and a dielectric layer of MWCNT/Ecoflex with a variable high dielectric constant under pressure, the pressure sensor exhibits linearity (R² = 0.990) within the pressure range of 0–60 kPa, boasting a sensitivity of 0.75 kPa⁻¹. Secondly, the sensor exhibits a rapid response time of 95 ms, a recovery time of 129 ms, hysteresis of 6.6%, and stability over 500 cycles. Moreover, the sensor effectively exhibited comprehensive detection of physiological signals, airflow detection, and Morse code communication, thereby demonstrating the potential for various applications. Full article

(This article belongs to the Special Issue Polymer-Based Flexible Materials)

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11 pages, 2745 KiB

Open AccessArticle

The Design, Synthesis, and Characterization of Epoxy Vitrimers with Enhanced Glass Transition Temperatures

by Chunai Dai, Yang Shi, Zhen Li, Tingting Hu, Xiao Wang, Yi Ding, Luting Yan, Yaohua Liang, Yingze Cao and Pengfei Wang

Polymers 2023, 15(22), 4346; https://doi.org/10.3390/polym15224346 - 7 Nov 2023

Cited by 5 | Viewed by 2451

Abstract

A series of epoxy vitrimers (EVs) with enhanced glass transition temperatures (T_gs) were synthesized by curing epoxy resin E51 with different ratios of phthalic anhydride and sebacic acid as curing agents, and 1,5,7-triazabicyclic [4.4.0] dece-5-ene as a transesterification catalyst, and [...] Read more.

A series of epoxy vitrimers (EVs) with enhanced glass transition temperatures (T_gs) were synthesized by curing epoxy resin E51 with different ratios of phthalic anhydride and sebacic acid as curing agents, and 1,5,7-triazabicyclic [4.4.0] dece-5-ene as a transesterification catalyst, and their curing dynamics, rheological properties, mechanical properties, and thermal stability were comprehensively investigated. By adjusting the molar ratio of the anhydride to the carboxylic acid in the curing agent, the T_gs of the EVs increased from 79 to 143 °C with the increase in the anhydride content. In particular, the material EV-5.5 with a high usable T_g of 98 °C could undergo stress relaxation through the transesterification reaction when exposed to high temperatures (160 to 200 °C), and the correlation between the relaxation time and temperature follows the Arrhenius equation. Moreover, EV-5.5 exhibited elastomeric behavior, where brittle fractures occurred before yielding, which demonstrated a tensile strength of 52 MPa. EV-5.5 also exhibited good thermal stability with a decomposition temperature (T_d5) of 322 °C. This study introduces new possibilities for practical applications of thermoset epoxy resins under special environmental conditions. Full article

(This article belongs to the Special Issue Polymer-Based Flexible Materials)

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15 pages, 5464 KiB

Open AccessArticle

A Comparative Study on the Properties of Rosin-Based Epoxy Resins with Different Flexible Chains

by Lianli Deng, Zehua Wang, Bailu Qu, Ying Liu, Wei Qiu and Shaohe Qi

Polymers 2023, 15(21), 4246; https://doi.org/10.3390/polym15214246 - 28 Oct 2023

Cited by 4 | Viewed by 1739

Abstract

This study aims to reveal the effects of flexible chain lengths on rosin-based epoxy resin’s properties. Two rosin-based epoxy monomers with varying chain lengths were synthesized: AR-EGDE (derived from ethylene glycol diglycidyl ether-modified acrylic acid rosin) and ARE (derived from acrylic acid rosin [...] Read more.

This study aims to reveal the effects of flexible chain lengths on rosin-based epoxy resin’s properties. Two rosin-based epoxy monomers with varying chain lengths were synthesized: AR-EGDE (derived from ethylene glycol diglycidyl ether-modified acrylic acid rosin) and ARE (derived from acrylic acid rosin and epichlorohydrin). Diethylenetriamine (DETA), triethylenetetramine (TETA), and tetraethylenepentamine (TEPA) with different flexible chain lengths were used as curing agents. The adhesion, impact, pencil hardness, flexibility, water and heat resistance, and weatherability of the epoxy resins were systematically examined. It was found that when the flexible chains of rosin-based epoxy monomers were grown from ARE to AR-EGDE, due to the increased space of rosin-based fused rings, the toughness, adhesion, and water resistance of the rosin-based epoxy resins were enhanced, while the pencil hardness and heat resistance decreased. However, when the flexible chains of curing agents were lengthened, the resin’s performance did not change significantly because the space between the fused rings changed little. This indicates that the properties of the rosin-based resins can only be altered when the introduced flexible chain increases the space between the fused rings. The study also compared rosin-based resins to E20, a commercial petroleum-based epoxy of the bisphenol A type. The rosin-based resins demonstrated superior adhesion, water resistance, and weatherability compared to the E20 resins, indicating the remarkable durability of the rosin-based resin. Full article

(This article belongs to the Special Issue Polymer-Based Flexible Materials)

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13 pages, 8445 KiB

Open AccessArticle

Effects of Electron Irradiation and Temperature on Mechanical Properties of Polyimide Film

by Jian Qiu, Jusha Ma, Wenjia Han, Xiao Wang, Xunchun Wang, Maliya Heini, Bingyang Li, Dongyang Sun, Ruifeng Zhang, Yan Shi and Cunfa Gao

Polymers 2023, 15(18), 3805; https://doi.org/10.3390/polym15183805 - 18 Sep 2023

Cited by 1 | Viewed by 1547

Abstract

Polyimide (PI) is widely deployed in space missions due to its good radiation resistance and durability. The influences from radiation and harsh temperatures should be carefully evaluated during the long-term service life. In the current work, the coupled thermal and radiation effects on [...] Read more.

Polyimide (PI) is widely deployed in space missions due to its good radiation resistance and durability. The influences from radiation and harsh temperatures should be carefully evaluated during the long-term service life. In the current work, the coupled thermal and radiation effects on the mechanical properties of PI samples were quantitatively investigated via experiments. At first, various PI specimens were prepared, and electron irradiation tests were conducted with different fluences. Then, both uniaxial tensile tests at room temperature and the dynamic mechanical analysis at varied temperatures of PI specimens with and without electron irradiation were performed. After that, uniaxial tensile tests at low and high temperatures were performed. The fracture surface of the PI film was observed using a scanning electron microscope, and its surface topography was measured using atomic force microscopy. In the meantime, the Fourier-transform infrared spectrum tests were conducted to check for chemical changes. In conclusion, the tensile tests showed that electron irradiation has a negligible effect during the linear stretching period but significantly impacts the hardening stage and elongation at break. Moreover, electron irradiation slightly influences the thermal properties of PI according to the differential scanning calorimetry results. However, both high and low temperatures dramatically affect the elastic modulus and elongation at break of PI. Full article

(This article belongs to the Special Issue Polymer-Based Flexible Materials)

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13 pages, 4219 KiB

Open AccessArticle

Fabrication of Highly Conductive Porous Fe₃O₄@RGO/PEDOT:PSS Composite Films via Acid Post-Treatment and Their Applications as Electrochemical Supercapacitor and Thermoelectric Material

by Luyao Gao, Fuwei Liu, Qinru Wei, Zhiwei Cai, Jiajia Duan, Fuqun Li, Huiying Li, Ruotong Lv, Mengke Wang, Jingxian Li and Letian Wang

Polymers 2023, 15(16), 3453; https://doi.org/10.3390/polym15163453 - 18 Aug 2023

Cited by 2 | Viewed by 1915

Abstract

As a remarkable multifunctional material, ferroferric oxide (Fe₃O₄) exhibits considerable potential for applications in many fields, such as energy storage and conversion technologies. However, the poor electronic and ionic conductivities of classical Fe₃O₄ restricts its application. [...] Read more.

As a remarkable multifunctional material, ferroferric oxide (Fe₃O₄) exhibits considerable potential for applications in many fields, such as energy storage and conversion technologies. However, the poor electronic and ionic conductivities of classical Fe₃O₄ restricts its application. To address this challenge, Fe₃O₄ nanoparticles are combined with graphene oxide (GO) via a typical hydrothermal method, followed by a conductive wrapping using poly(3,4-ethylenedioxythiophene):poly(styrene sulfonic sulfonate) (PEDOT:PSS) for the fabrication of composite films. Upon acid treatment, a highly conductive porous Fe₃O₄@RGO/PEDOT:PSS hybrid is successfully constructed, and each component exerts its action that effectively facilitates the electron transfer and subsequent performance improvement. Specifically, the Fe₃O₄@RGO/PEDOT:PSS porous film achieves a high specific capacitance of 244.7 F g⁻¹ at a current of 1 A g⁻¹. Furthermore, due to the facial fabrication of the highly conductive networks, the free-standing film exhibits potential advantages in flexible thermoelectric (TE) materials. Notably, such a hybrid film shows a high electric conductivity (σ) of 507.56 S cm⁻¹, a three times greater value than the Fe₃O₄@RGO component, and achieves an optimized Seebeck coefficient (S) of 13.29 μV K⁻¹ at room temperature. This work provides a novel route for the synthesis of Fe₃O₄@RGO/PEDOT:PSS multifunctional films that possess promising applications in energy storage and conversion. Full article

(This article belongs to the Special Issue Polymer-Based Flexible Materials)

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10 pages, 2876 KiB

Open AccessArticle

Flexible Wet-Spun PEDOT:PSS Microfibers Integrating Thermal-Sensing and Joule Heating Functions for Smart Textiles

by Yan Li, Hongwei Hu, Teddy Salim, Guanggui Cheng, Yeng Ming Lam and Jianning Ding

Polymers 2023, 15(16), 3432; https://doi.org/10.3390/polym15163432 - 17 Aug 2023

Cited by 3 | Viewed by 1866

Abstract

Multifunctional fiber materials play a key role in the field of smart textiles. Temperature sensing and active thermal management are two important functions of smart fabrics, but few studies have combined both functions in a single fiber material. In this work, we demonstrate [...] Read more.

Multifunctional fiber materials play a key role in the field of smart textiles. Temperature sensing and active thermal management are two important functions of smart fabrics, but few studies have combined both functions in a single fiber material. In this work, we demonstrate a temperature-sensing and in situ heating functionalized conductive polymer microfiber by exploiting its high electrical conductivity and thermoelectric properties. The conductive polymer microfibers were prepared by wet-spinning the PEDOT:PSS aqueous dispersion with ionic liquid additives, which was used to enhance the electrical and mechanical properties of the final microfibers. The thermoelectric properties of these microfibers were further studied. Due to their excellent flexibility and mechanical properties, these fibers can be easily integrated into commercial fabrics for the manufacture of smart textiles through knitting. We further demonstrated a smart glove with integrated temperature-sensing and in situ heating functions, and further explored thermoelectric fiber-based temperature-sensing array fabric. These works combine the thermoelectric properties and heating function of conductive polymer fibers, providing new insights that enable further development of high-performance, multifunctional wearable smart textiles. Full article

(This article belongs to the Special Issue Polymer-Based Flexible Materials)

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16 pages, 3663 KiB

Open AccessArticle

Flexible BaTiO₃-PDMS Capacitive Pressure Sensor of High Sensitivity with Gradient Micro-Structure by Laser Engraving and Molding

by Jiayi Li, Shangbi Chen, Jingyu Zhou, Lei Tang, Chenkai Jiang, Dawei Zhang and Bin Sheng

Polymers 2023, 15(15), 3292; https://doi.org/10.3390/polym15153292 - 3 Aug 2023

Cited by 2 | Viewed by 2527

Abstract

The significant potential of flexible sensors in various fields such as human health, soft robotics, human–machine interaction, and electronic skin has garnered considerable attention. Capacitive pressure sensor is popular given their mechanical flexibility, high sensitivity, and signal stability. Enhancing the performance of capacitive [...] Read more.

The significant potential of flexible sensors in various fields such as human health, soft robotics, human–machine interaction, and electronic skin has garnered considerable attention. Capacitive pressure sensor is popular given their mechanical flexibility, high sensitivity, and signal stability. Enhancing the performance of capacitive sensors can be achieved through the utilization of gradient structures and high dielectric constant media. This study introduced a novel dielectric layer, employing the BaTiO₃-PDMS material with a gradient micro-cones architecture (GMCA). The capacitive sensor was constructed by incorporating a dielectric layer GMCA, which was fabricated using laser engraved acrylic (PMMA) molds and flexible copper-foil/polyimide-tape electrodes. To examine its functionality, the prepared sensor was subjected to a pressure range of 0–50 KPa. Consequently, this sensor exhibited a remarkable sensitivity of up to 1.69 KPa⁻¹ within the pressure range of 0–50 KPa, while maintaining high pressure-resolution across the entire pressure spectrum. Additionally, the pressure sensor demonstrated a rapid response time of 50 ms, low hysteresis of 0.81%, recovery time of 160 ms, and excellent cycling stability over 1000 cycles. The findings indicated that the GMCA pressure sensor, which utilized a gradient structure and BaTiO₃-PDMS material, exhibited notable sensitivity and a broad linear pressure range. These results underscore the adaptability and viability of this technology, thereby facilitating enhanced flexibility in pressure sensors and fostering advancements in laser manufacturing and flexible devices for a wider array of potential applications. Full article

(This article belongs to the Special Issue Polymer-Based Flexible Materials)

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32 pages, 7369 KiB

Open AccessArticle

A Modified Constitutive Model for Isotropic Hyperelastic Polymeric Materials and Its Parameter Identification

by Wei Wang, Yang Liu and Zongwu Xie

Polymers 2023, 15(15), 3172; https://doi.org/10.3390/polym15153172 - 26 Jul 2023

Cited by 4 | Viewed by 1639

Abstract

Given the importance of hyperelastic constitutive models in the design of engineering components, researchers have been developing the improved and new constitutive models in search of a more accurate and even universal performance. Here, a modified hyperelastic constitutive model based on the Yeoh [...] Read more.

Given the importance of hyperelastic constitutive models in the design of engineering components, researchers have been developing the improved and new constitutive models in search of a more accurate and even universal performance. Here, a modified hyperelastic constitutive model based on the Yeoh model is proposed to improve its prediction performance for multiaxial deformation of hyperelastic polymeric materials while retaining the advantages of the original Yeoh model. The modified constitutive model has one more correction term than the original model. The specific form of the correction term is a composite function based on a power function represented by the principal stretches, which is derived from the corresponding residual strain energy when the Yeoh model predicts the equibiaxial mode of deformation. In addition, a parameter identification method based on the cyclic genetic-pattern search algorithm is introduced to accurately obtain the parameters of the constitutive model. By applying the modified model to the experimental datasets of various rubber or rubber-like materials (including natural unfilled or filled rubber, silicone rubber, extremely soft hydrogel and human brain cortex tissue), it is confirmed that the modified model not only possesses a significantly improved ability to predict multiaxial deformation, but also has a wider range of material applicability. Meanwhile, the advantages of the modified model over most existing models in the literatures are also demonstrated. For example, when characterizing human brain tissue, which is difficult for most existing models in the literature, the modified model has comparable predictive accuracy with the third-order Ogden model, while maintaining convexity in the corresponding deformation domain. Moreover, the effective prediction ability of the modified model for untested equi-biaxial deformation of different materials has also been confirmed using only the data of uniaxial tension and pure shear from various datasets. The effective prediction for the untested equibiaxial deformation makes it more suitable for the practice situation where the equibiaxial deformation of certain polymeric materials is unavailable. Finally, compared with other parameter identification methods, the introduced parameter identification method significantly improves the predicted accuracy of the constitutive models; meanwhile, the uniform convergence of introduced parameter identification method is also better. Full article

(This article belongs to the Special Issue Polymer-Based Flexible Materials)

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17 pages, 4758 KiB

Open AccessArticle

Phase Change Microcapsule Composite Material with Intelligent Thermoregulation Function for Infrared Camouflage

by Ying Su, Xiaoming Zhao and Yue Han

Polymers 2023, 15(14), 3055; https://doi.org/10.3390/polym15143055 - 15 Jul 2023

Cited by 6 | Viewed by 2241

Abstract

The infrared camouflage textile materials with soft and wear-resistant properties can effectively reduce the possibility of soldiers and military equipment being exposed to infrared detectors. In this paper, the infrared camouflage textile composites with intelligent temperature adjustment ability were prepared by different methods, [...] Read more.

The infrared camouflage textile materials with soft and wear-resistant properties can effectively reduce the possibility of soldiers and military equipment being exposed to infrared detectors. In this paper, the infrared camouflage textile composites with intelligent temperature adjustment ability were prepared by different methods, using phase change microcapsule as the main raw material and high polymer polyurethane as the matrix, combining the two factors of temperature control and emissivity reduction. It was tested by differential scanning calorimeter, temperature change tester, infrared emissivity tester, and infrared imager. The results show that the temperature regulation effect of textile materials finished by coating method is better than dip rolling method, the temperature regulation ability and presentation effect are the best when the microcapsule content is 27%. When the bottom layer of infrared camouflage textile composite is 27% phase change microcapsule and the surface layer is 20% copper powder, its infrared emissivity in the band of 2–22 μm is 0.656, and the rate of heating and cooling is obviously slowed down. It has excellent heat storage and temperature regulation function, which can reduce the skin surface temperature by more than 6 °C and effectively reduce the infrared radiation. This study can provide reference for laboratory preparation and industrial production of infrared camouflage composite material. The infrared camouflage textile composite prepared are expected to be used in the field of military textiles. Full article

(This article belongs to the Special Issue Polymer-Based Flexible Materials)

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11 pages, 5443 KiB

Open AccessArticle

Wearable Pressure Sensor Using Porous Natural Polymer Hydrogel Elastomers with High Sensitivity over a Wide Sensing Range

by Fan Xiao, Shunyu Jin, Wan Zhang, Yingxin Zhang, Hang Zhou and Yuan Huang

Polymers 2023, 15(12), 2736; https://doi.org/10.3390/polym15122736 - 19 Jun 2023

Cited by 9 | Viewed by 2080

Abstract

Wearable pressure sensors capable of quantifying full-range human dynamic motionare are pivotal in wearable electronics and human activity monitoring. Since wearable pressure sensors directly or indirectly contact skin, selecting flexible soft and skin-friendly materials is important. Wearable pressure sensors with natural polymer-based hydrogels [...] Read more.

Wearable pressure sensors capable of quantifying full-range human dynamic motionare are pivotal in wearable electronics and human activity monitoring. Since wearable pressure sensors directly or indirectly contact skin, selecting flexible soft and skin-friendly materials is important. Wearable pressure sensors with natural polymer-based hydrogels are extensively explored to enable safe contact with skin. Despite recent advances, most natural polymer-based hydrogel sensors suffer from low sensitivity at high-pressure ranges. Here, by using commercially available rosin particles as sacrificial templates, a cost-effective wide-range porous locust bean gum-based hydrogel pressure sensor is constructed. Due to the three-dimensional macroporous structure of the hydrogel, the constructed sensor exhibits high sensitivities (12.7, 5.0, and 3.2 kPa⁻¹ under 0.1–20, 20–50, and 50–100 kPa) under a wide range of pressure. The sensor also offers a fast response time (263 ms) and good durability over 500 loading/unloading cycles. In addition, the sensor is successfully applied for monitoring human dynamic motion. This work provides a low-cost and easy fabrication strategy for fabricating high-performance natural polymer-based hydrogel piezoresistive sensors with a wide response range and high sensitivity. Full article

(This article belongs to the Special Issue Polymer-Based Flexible Materials)

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11 pages, 14393 KiB

Open AccessArticle

The Mechanical Properties of Silicone Rubber Composites with Shear Thickening Fluid Microcapsules

by Chun Wei, Xiaofei Hao, Chaoying Mao, Fachun Zhong and Zhongping Liu

Polymers 2023, 15(12), 2704; https://doi.org/10.3390/polym15122704 - 16 Jun 2023

Cited by 6 | Viewed by 2500

Abstract

In this study, Sylgard 184 silicone rubber (SylSR) matrix composites with shear thickening fluid (STF) microcapsules (SylSR/STF) were fabricated. Their mechanical behaviors were characterized by dynamic thermo-mechanical analysis (DMA) and quasi-static compression. Their damping properties increased with the addition ofSTF into the SR [...] Read more.

In this study, Sylgard 184 silicone rubber (SylSR) matrix composites with shear thickening fluid (STF) microcapsules (SylSR/STF) were fabricated. Their mechanical behaviors were characterized by dynamic thermo-mechanical analysis (DMA) and quasi-static compression. Their damping properties increased with the addition ofSTF into the SR in DMA tests and the SylSR/STF composites presented decreased stiffness and an obvious positive strain rate effect in the quasi-static compression test. Moreover, the impact resistance behavior of the SylSR/STF composites was tested by the drop hammer impact test. The addition of STF enhanced the impact protective performance of silicone rubber, and the impact resistance increased with the increase of STF content, which should be ascribed to the shear thickening and energy absorption of STF microcapsules in the composites. Meanwhile, in another matrix, hot vulcanized silicone rubber (HTVSR) with a mechanical strength higher than Sylgard 184, the impact resistance capacity of its composite with STF (HTVSR/STF) was also examined by the drop hammer impact test. It is interesting to note that the strength of the SR matrix obviously influenced the enhancement effect of STF on the impact resistance of SR. The stronger the strength of SR, the better the effect of STF on improving the impact protective performance of SR. This study not only provides a new method for packaging STF and improving the impact resistance behavior of SR, but is also beneficial for the design of STF-related protective functional materials and structures. Full article

(This article belongs to the Special Issue Polymer-Based Flexible Materials)

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25 pages, 10927 KiB

Open AccessArticle

Interaction Mechanism of Composite Propellant Components under Heating Conditions

by Jiahao Liang, Jianxin Nie, Haijun Zhang, Xueyong Guo, Shi Yan and Ming Han

Polymers 2023, 15(11), 2485; https://doi.org/10.3390/polym15112485 - 28 May 2023

Cited by 5 | Viewed by 1795

Abstract

To examine the interactions between two binder systems—hydroxyl-terminated polybutadiene (HTPB) and hydroxyl-terminated block copolyether prepolymer (HTPE)—as well as between these binders and ammonium perchlorate (AP) at various temperatures for their susceptibility to varying degrees of thermal damage treatment, the thermal characteristics and combustion [...] Read more.

To examine the interactions between two binder systems—hydroxyl-terminated polybutadiene (HTPB) and hydroxyl-terminated block copolyether prepolymer (HTPE)—as well as between these binders and ammonium perchlorate (AP) at various temperatures for their susceptibility to varying degrees of thermal damage treatment, the thermal characteristics and combustion interactions of the HTPB and HTPE binder systems, HTPB/AP and HTPE/AP mixtures, and HTPB/AP/Al and HTPE/AP/Al propellants were studied. The results showed that the first and second weight loss decomposition peak temperatures of the HTPB binder were, respectively, 85.34 and 55.74 °C higher than the HTPE binder. The HTPE binder decomposed more easily than the HTPB binder. The microstructure showed that the HTPB binder became brittle and cracked when heated, while the HTPE binder liquefied when heated. The combustion characteristic index, S, and the difference between calculated and experimental mass damage, ΔW, indicated that the components interacted. The original S index of the HTPB/AP mixture was 3.34 × 10⁻⁸; S first decreased and then increased to 4.24 × 10⁻⁸ with the sampling temperature. Its combustion was initially mild, then intensified. The original S index of the HTPE/AP mixture was 3.78 × 10⁻⁸; S increased and then decreased to 2.78 × 10⁻⁸ with the increasing sampling temperature. Its combustion was initially rapid, then slowed. Under high-temperature conditions, the HTPB/AP/Al propellants combusted more intensely than the HTPE/AP/Al propellants, and its components interacted more strongly. A heated HTPE/AP mixture acted as a barrier, reducing the responsiveness of solid propellants. Full article

(This article belongs to the Special Issue Polymer-Based Flexible Materials)

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Review

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17 pages, 5112 KiB

Open AccessReview

Research Status of and Prospects for 3D Printing for Continuous Fiber-Reinforced Thermoplastic Composites

by Yuan Yang, Bo Yang, Zhengping Chang, Jihao Duan and Weihua Chen

Polymers 2023, 15(17), 3653; https://doi.org/10.3390/polym15173653 - 4 Sep 2023

Cited by 8 | Viewed by 3193

Abstract

Continuous fiber-reinforced thermoplastic composites (CFRTPCs) have advantages such as high specific strength, high specific modulus, corrosion resistance, and recyclability and are widely used in the fields of aerospace, rail transit, new energy, and so on. However, traditional methods for preparing CFRTPCs, such as [...] Read more.

Continuous fiber-reinforced thermoplastic composites (CFRTPCs) have advantages such as high specific strength, high specific modulus, corrosion resistance, and recyclability and are widely used in the fields of aerospace, rail transit, new energy, and so on. However, traditional methods for preparing CFRTPCs, such as placement and molding, rely more on forming molds, resulting in high manufacturing costs and a slow response speed, which limits the promotion and application of the new generation of CFRTPCs with complex configurations and designable performance. Three-dimensional printing can efficiently create products with multiple materials, complex structures, and integrated functions, introducing new ways and opportunities for the manufacturing of CFRTPCs. However, poor mechanical properties are the bottleneck problem in achieving 3D printing of CFRTPCs. This paper summarizes the research status of the fused deposition modeling (FDM) 3D printing process and the corresponding mechanical properties of CFRTPCs. The focus is on analyzing the influences of the FDM process parameters, such as the material type, printing temperature, speed parameters, layer thickness, scanning space, stacking direction, and fiber volume content, on the mechanical properties of CFRTPCs. Finally, the main problems and future prospects of current CFRTPCs-FDM are analyzed and forecasted, providing new references and ideas for 3D printing of high-performance CFRTPCs. Full article

(This article belongs to the Special Issue Polymer-Based Flexible Materials)

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