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1.
紫外光固化聚氨酯丙烯酸酯树脂的流变行为 总被引:6,自引:0,他引:6
合成了一系列紫外光因化聚氨酯丙烯酸酯聚合物,研究了分子量、原料配比、反应方式、含水量、溶剂等对其流变行为的影响。实验表明,控制剂聚物分子量,干燥原料,以HEA先与异氰酸酯反应的加料方式合成的树脂,流动性较好。在此基础上合成了较好流动性和光固化性能的蓖麻油紫外光固化树脂。 相似文献
2.
UV-curable silicones are a highly specialised class of compounds that can be applied in various applications e.g. as additives in UV-curable inks and coatings or as release coatings on paper and plastic substrates. Basically two classes of radiation curable silicones are available on the market today. Both, the free radical and the cationic curing process, offer each unique advantages to the customer. Applied as additives in UV-curable inks and coatings they offer several advantages such as improved wetting behaviour, scratch resistance, flow and levelling of the UV-curable inks and coatings. Additionally, the efficient cross-linking properties minimise the risk of migration. 相似文献
3.
Siwaporn Srimongkol Panithi Wiroonpochit Kittaporn Utra Rathanakarn Sethayospongsa Pennapa Muthitamongkol Boriphat Methachan Natsaporn Butsri Sasitorn Srisawadi 《先进技术聚合物》2023,34(1):287-298
Polymeric-based flexible electronic devices are in high demand due to its wide range of applications. Natural rubber (NR) shows a great potential as matrix phase for flexible conductive polymer composites with its high elasticity and fatigue resistance. In this study, a new 3D printable conductive NR (CNR) composite was developed for strain sensor applications. Different contents of conductive carbon black (CCB) were mixed with NR latex to investigate the effect of the filler content on electrical and mechanical properties of the composites. The best-known CNR composite with the CCB content of 12 phr was selected in order to produce the feedstock for the stereolithography process (SLA). The morphological, electrical, and mechanical properties of cast and 3D-printed samples were investigated and compared. Although the 3D-printed CNR sample had slightly lower conductivity than the cast one, it possessed comparable tensile strength and elongation at break, with values of 12.4 MPa and 703%, respectively. In addition, electrical responses of the CNR samples were investigated to demonstrate the electromechanical property of the material as a strain sensor. The 3D-printed CNR sample exhibited the highest electromechanical sensitivity with a gauge factor (GF) of 361.4 (ε = 210%–300%) and showed good repeatability for 500 cycles. In conclusion, the development of this 3D printable functional material with great sensing capability will pave the way for innovative designs of personalized sensing textiles and other smart wearable devices. 相似文献
4.
L. Saitta G. Montalbano I. Corvaglia C. Vitale Brovarone G. Cicala 《Macromolecular Symposia》2023,411(1):2200188
This study presents an upscaling re-use strategy for a recycled thermoplastic which is obtained starting from a chemical recycling approach for a bio-based fully-recyclable epoxy resin system. The recycling approach used relies on the selective cleaving of the epoxy-cured network under mild conditions. The re-use strategy proposed in this work consists in the use of the recycled thermoplastic (rTP), as obtained at the end of the recycling process and without any additional treatments, as raw material for a 3D printing process falling within the material extrusion category. The used 3D printing technique relies on the use of a thermoplastic printhead equipped with a metallic cartridge, fillable with the rTP material, to which a suitable pressure value is applied in order to start the extrusion process. The recycled material is characterized through thermal and rheological analysis in order to find the correct printing conditions, such as extrusion temperature and pressure applied. Next, the printability of specimens having different type of infill is investigated and the µCT analysis is used to evaluate the quality of the 3D printed samples. 相似文献
5.
Min Jeong Lee Sung Eun Kim Juri Park Guk Young Ahn Tae Hoon Yun Inseong Choi Hak‐Jun Kim Sung‐Wook Choi 《先进技术聚合物》2019,30(12):3083-3090
We described the curcumin‐loaded biodegradable polyurethane (PU) scaffolds modified with gelatin based on three‐dimensional (3D) printing technology for potential application of cartilage regeneration. The printing solution of poly(ε‐caprolactone) (PCL) triol (polyol) and hexamethylene diisocyanate (HMDI) in 2,2,2‐trifluoroethanol was printed through a nozzle in dimethyl sulfoxide phase with or without gelatin. The weight ratio of HMDI against PCL triol was varied as 3, 5, and 7 in order to evaluate its effect on the mechanical properties and biodegradation rate. A higher ratio of HMDI resulted in higher mechanical properties and a lower biodegradation rate. The use of gelatin increased the mechanical properties, biodegradation rate, and curcumin release due to the surface cross‐linking, nanoporous structure, and surface hydrophilicity of the scaffolds. In vitro study revealed that the released curcumin enhanced the proliferation and differentiation of chondrocyte. The 3D‐printed biodegradable PU scaffold modified with gelatin should thus be considered as a potential candidate for cartilage regeneration. 相似文献
6.
Hannah Buchheit Bernd Bruchmann Klaus Stoll Rolf Mülhaupt 《Journal of polymer science. Part A, Polymer chemistry》2021,59(10):882-892
Liquid urethane (meth)acrylates represent attractive components of photocurable thermosets for applications ranging from coatings and adhesives to 3D printing. Herein we tailor liquid polyfunctional urethane methacrylates (UMA) derived from acrylic polyhydroxy urethanes. Cyclic carbonate methacrylates react with diamines to form dihydroxy-functional urethane dimethacrylates. In an “one-pot” process the hydroxy groups are functionalized either by reaction with 2-isocyanatoethyl methacrylate (IEMA) or by esterification with methacrylic anhydride (MAA) and acetic anhydride (AA). The hydroxy group esterification substantially lowers the resin viscosity (26–156 Pa•s). Hydroxy functionalization with IEMA and MAA affords tetrafunctional methacrylates. The corresponding photo-cured thermosets exhibit higher crosslinking density and improved stiffness as reflected by increasing the Young's modulus from 2900 to 3700 MPa combined with increasing the glass temperature from 135 to 204°C. Hence, this facile molecular UMA design enables to control functionality and thermoset properties over a wide range and meets the demands of 3D printing applications. 相似文献
7.
Polyurethane (PU) and polyurethane acrylate (PUA) networks based on hydroxyl-terminated polycaprolactone (PCL), 1,3-bis-2,2′(2-isocyanatopropyl)benzene (m-TMXDI), trimethylolpropane (TMP) for PU or hydroxyethyl methacrylate (HEMA) for PUA were synthesized. Glass transition temperature, Tg, dynamic mechanical relaxation, α, and equilibrium tensile modulus, E′, were measured to compare the two kinds of networks. To explain thermal and mechanical properties of networks, the concept of hard clusters has been introduced. PU networks exhibit a single-phase structure with modulus and Tg dependent on the concentration of elastically active network chains (EANC) per unit volume calculated by considering hard crosslink clusters. The rigidity of the clusters comes from small diisocyanate and trimethylolpropane units connected by urethane bonds. They are embedded in a continuous soft phase of macrodiol urethane. Physical equivalence between several kinds of network models has been demonstrated for full conversion of isocyanate-alcohol reaction. PUA networks exhibit thermodynamically one-phase structures that become a two-phase structure for high molar mass of macrodiol when the molar fraction of isocyanate groups increases. For those networks, the calculated modulus considering clusters based on polyacrylate chains seems to be a good way to approach the experimental value of the equilibrium modulus. For the same molar ratio of OH to NCO groups the range of dynamic moduli is larger for PUA than for PU. This difference can be explained by a different concentration of crosslinks in the networks. © 1996 John Wiley & Sons, Inc. 相似文献
8.
将磺酸型聚酯多元醇、异佛尔酮二异氰酸酯(IPDI)和三羟甲基丙烷(TMP)在无有机溶剂参与的情况下进行预缩聚,以硅烷偶联剂γ-氨丙基三乙氧基硅烷(KH550)作为改性剂,加入双官能团单体甲基丙烯酸-β-羟乙酯(HEMA),得到含乙烯基和有机硅封端的聚氨酯作为种子乳液,然后与甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)混合单体共聚,合成了有机硅改性磺酸型聚氨酯/丙烯酸酯复合乳液。 红外光谱的表征确定了有机硅改性磺酸型聚氨酯/丙烯酸酯复合乳液的化学结构;透射电子显微镜观察证实了此复合乳液具有明显的核壳结构;热重分析表明,经有机硅和丙烯酸酯改性后,胶膜的最大热失重温度提高了20 ℃,X射线衍射分析表明胶膜的结晶度降低,有利于提高膜的韧性。 力学性能测试及吸水率测试结果表明,当有机硅含量为1.9%时,胶膜的拉伸强度最高达到25.03 MPa,断裂伸长率为328%,此时膜的吸水率最低。 相似文献
9.
Metamaterials are specifically designed materials that possess unique properties that cannot be found in naturally occurring substances. These remarkable materials have the capability to bring about a significant transformation across a wide range of industries. Auxetic structures are a recent area of research possess a distinctive characteristic known as a negative Poisson's ratio. Unlike conventional materials that contract when stretched, auxetic structures actually expand in two dimensions. In this study, a new auxetic structure was introduced, and thermoplastic polyurethane samples were 3D printed using a fused filament fabrication method. The samples are then subjected to strains ranging from 5% to 50% and Poisson's ratios are measured both experimentally and numerically using finite element method in Ansys software. By comparing the results of the experimental research and simulation, it is evident that applying strains within this range causes the Poisson's ratio of the samples to change from −0.81 to −0.14 and it showed that the newly introduced structure is auxetic. According to the analysis of root mean square error, the hexagonal mesh with a size of 0.7 mm consistently produced the most accurate results, aligning closely with the experimental sample. Given that this is an entirely novel auxetic structure within the category of arrow-head auxetic structures, there is potential for future research to be conducted in order to further develop and enhance this model. 相似文献
10.
A carbon black (CB) photo resist, comprising CB, CB dispersant, photo-curable resin, photo-initiator, and solvent, has been developed in order to prepare a light-shielding black matrix (BM) in the liquid crystal display application. In order to prepare a BM with a high opacity property or optical density (OD), the effect of CB such as its particle and concentration on light absorption property was first evaluated, and the results showed that 45 wt% CB with a particle size of about 100 nm in BM could reach an OD value of 4 μm−1. Moreover, six different UV-curable and alkali-soluble resins (A1, A2, and A3; B1, B2, and B3) were synthesized as photo-curable resins. Structures of these resins were characterized by FTIR and GPC, in which concentrations of various functional groups, especially carboxylic acid and double bond, were calculated. Subsequently, their photo-initiated polymerization rate with or without CB were measured. Finally, it was found that through a proper selection of the newly synthesized resins to prepare a carbon black photo resist, a BM with an OD of 4 μm−1 and a good resolution of 10 μm was successfully prepared upon low UV irradiation energy of 50 mJ/cm2. 相似文献
11.
Effect of zinc soaps of rubber seed oil (RSO) and/or epoxidised rubber seed oil (ERSO) on the thermal stability of PVC plastigels 总被引:2,自引:0,他引:2
Theresa Obuajulu Egbuchunam Felix Ebhodaghe Okieimen 《Polymer Degradation and Stability》2007,92(8):1572-1582
Zinc soaps of rubber seed oil (RSO) and epoxidised rubber seed oil (ERSO) were prepared and their use as PVC stabilizers investigated. Characterization of Zn soaps of RSO prepared by different techniques and ERSO gave information on the purity, structure and thermal behaviour of these materials. From the analysis, the production of these materials for use in thermal stabilization of PVC would be optimized as their use greatly enhanced the stability of PVC as obtained from the conductivity measurements using the 763 PVC Thermomat. The minimum amount of HCl release was obtained for the samples with Zn soaps and ERSO indicating a synergistic effect. Zn soaps having Zn(OH)2 stabilized PVC better than pure Zn soaps. 相似文献
12.
Vikash Mishra Ishan Mohanty Mayank R. Patel 《International Journal of Polymer Analysis and Characterization》2015,20(6):504-513
A series of novel waterborne UV-curable polyurethane dispersions were synthesized from castor oil, IPDI, DMPA, and HEMA by the acetone process. The prepared UV-PUD was mixed with three different monomers and characterized for the parameters relevant to the study by physical, spectroscopic, and chemical methods. The effect of monomer type on the physicochemical and thermal properties of UV-PUDs revealed that the number of unsaturated groups present in the monomer had a pronounced effect on physicochemical, mechanical, and thermal properties. The combination of renewable resource and environmentally compliant technology give these UV-PUDs potential scope in coating applications. 相似文献
13.
Mario Bragaglia;Francesca Sciarretta;Pierfrancesco Filetici;Daniele Lettieri-Barbato;Leonardo Dassatti;Fabrizio Nicoletti;Diego Sibilia;Katia Aquilano;Francesca Nanni; 《Macromolecular bioscience》2024,24(5):2300458
This study aims to obtain a cyto-compatible 3D printable bio-resin for the manufacturing of meshes designed from acquired real patients’ bone defect to be used in future for guided bone regeneration (GBR), achieving the goal of personalized medicine, decreasing surgical, recovery time, and patient discomfort. To this purpose, a biobased, biocompatible, and photo-curable resin made of acrylated epoxidized soybean oil (AESO) diluted with soybean oil (SO) is developed and 3D printed using a commercial digital light processing (DLP) 3D printer. 3D printed samples show good thermal properties, allowing for thermally-based sterilization process and mechanical properties typical of crosslinked natural oils (i.e., E = 12 MPa, UTS = 1.5 MPa), suitable for the GBR application in the oral surgery. The AESO-SO bio-resin proves to be cytocompatible, allowing for fibroblast cells proliferation (viability at 72 h > 97%), without inducing severe inflammatory response when co-cultured with macrophages, as demonstrated by cytokine antibody arrays, that is anyway resolved in the first 24 h. Moreover, accelerated degradation tests prove that the bio-resin is biodegradable in hydrolytic environments. 相似文献
14.
Wei Yang Anqianyi Tu Yuchen Ma Zhanming Li Jie Xu Min Lin Kailong Zhang Linzhi Jing Caili Fu Yang Jiao Lingyi Huang 《Molecules (Basel, Switzerland)》2022,27(1)
The application of chitosan (CS) and whey protein (WP) alone or in combination in 3D/4D printing has been well considered in previous studies. Although several excellent reviews on additive manufacturing discussed the properties and biomedical applications of CS and WP, there is a lack of a systemic review about CS and WP bio-inks for 3D/4D printing applications. Easily modified bio-ink with optimal printability is a key for additive manufacturing. CS, WP, and WP–CS complex hydrogel possess great potential in making bio-ink that can be broadly used for future 3D/4D printing, because CS is a functional polysaccharide with good biodegradability, biocompatibility, non-immunogenicity, and non-carcinogenicity, while CS–WP complex hydrogel has better printability and drug-delivery effectivity than WP hydrogel. The review summarizes the current advances of bio-ink preparation employing CS and/or WP to satisfy the requirements of 3D/4D printing and post-treatment of materials. The applications of CS/WP bio-ink mainly focus on 3D food printing with a few applications in cosmetics. The review also highlights the trends of CS/WP bio-inks as potential candidates in 4D printing. Some promising strategies for developing novel bio-inks based on CS and/or WP are introduced, aiming to provide new insights into the value-added development and commercial CS and WP utilization. 相似文献
15.
16.
The work used bio‐polyol from rubber seed oil for rigid polyurethane synthesis. The water was used as the only blowing agent. FTIR spectrum demonstrated the formation of polyurethanes from bio‐polyol, glycerol, isocyanate and water. The effects of water, glycerol content and NCO/OH molar ratio on properties of foam were investigated through compression strength, density, average porous radius, size and distribution of cells. The suitable recipe for materials was chosen and the cream time, the rise time and the tack free time were also determined. The rigid polyurethane foam was synthesized at water and glycerol content of 4 and 3 wt.% of polyol, molar NCO/OH ratio of 0.8 had the compressive strength of 125.11 KPa, density of 62.75 kg/m3 and average porous radius of 237.52 μm. 相似文献
17.
Harald Rupp Diana Dhler Philipp Hilgeroth Nasir Mahmood Mario Beiner Wolfgang H. Binder 《Macromolecular rapid communications》2019,40(24)
3D printing of linear and three‐arm star supramolecular polymers with attached hydrogen bonds and their nanocomposites is reported. The concept is based on hydrogen‐bonded supramolecular polymers, known to form nano‐sized micellar clusters. Printability is based on reversible thermal‐ and shear‐induced dissociation of a supramolecular polymer network, which generates stable and self‐supported structures after printing, as checked via melt‐rheology and X‐ray scattering. The linear and three‐arm star poly(isobutylene)s PIB‐B2 (Mn = 8500 g mol −1), PIB‐B3 (Mn = 16 000 g mol −1), and linear poly(ethylene glycol)s PEG‐B2 (Mn = 900 g mol−1, 8500 g mol −1) are prepared and then probed by melt‐rheology to adjust the viscosity to address the proper printing window. The supramolecular PIB polymers show a rubber‐like behavior and are able to form self‐supported 3D printed objects at room temperature and below, reaching polymer strand diameters down to 200–300 µm. Nanocomposites of PIB‐B2 with silica nanoparticles (12 nm, 5–15 wt%) are generated, in turn leading to an improvement of their shape persistence. A blend of the linear polymer PIB‐B2 and the three‐arm star polymer PIB‐B3 (ratio ≈ 3/1 mol) reaches an even higher structural stability, able to build free‐standing structures. 相似文献
18.
He Lijuan;Kong Delong;Xu Caihong;Lei Chaoshuai;Li Wenjing;Zhao Yingmin 《化学进展》2021,32(12):1978-1989
3D printing to prepare ceramics can realize structure-material design integration,which provides new opportunities for rapid prototyping of ceramic materials with complex shapes. However,traditional 3D printing for preparing ceramics uses ceramic powder or ceramic particles as the printing material,which has problems such as poor dimensional accuracy of ceramic components,low surface finish,and poor mechanical properties. In recent years,the emergence of technology that uses polymer precursors to produce ceramic materials with complex shapes through processes of 3D printing molding and pyrolysis provides new methods to improve this situation. It has become one of the most popular research topics in the field of 3D printing to prepare ceramics. This article summarizes the research progress of 3D printing of polymer precursor derived high performance ceramics,focusing on research status of the five typical material systems: bulk polymer precursors,polymer precursors/photosensitive compounds blends,polymer precursors/thiol compounds blends,photosensitive group-modified polymer precursors,and reinforcement/polymer precursors. Besides,an outlook for future development of 3D printing of polymer precursor derived advanced ceramics is given. Contents 1 Introduction2 3D printing of polymer precursor derived ceramics2.1 Bulk polymer precursors2.2 Polymer precursors/photosensitive compounds blends2.3 Polymer precursors/thiol compounds blends2.4 Photosensitive group modified polymer precursors2.5 Reinforcement/polymer precursors3 Conclusion and outlook 相似文献
19.
Alex Chortos 《Journal of polymer science. Part A, Polymer chemistry》2022,60(3):486-503
Conjugated polymers combine electronic charge transport properties with the ability to transport ions, enabling transduction between ionic and electronic currents. Many applications of conjugated polymers, such as biointerfaces, actuators, and energy storage, benefit from 3D structures. Among different methods for 3D fabrication, extrusion-based 3D printing is a versatile approach that is compatible with multimaterial fabrication processes. This review summarizes progress in the emerging field of 3D printed conjugated polymers using three extrusion printing processes: direct ink write, meniscus-guided printing, and electrohydrodynamic printing. Ink designs for direct in write are described in depth, including strategies for modifying the rheology and conductivity of the inks. 相似文献
20.
Zhongying Ji Xiaoqin Zhang Changyou Yan Xin Jia Yanqiu Xia Xiaolong Wang Feng Zhou 《Macromolecular rapid communications》2019,40(8)
Three‐dimensional (3D) printing elastomers, as a combination of transformative technology and widely used materials, have received great demand in many fields. However, commercial photocuring elastomer inks for 3D printing usually exhibit poor mechanical strength, inferior resilience, and lower elongation at break. In this study, photocuring inks that can be employed for digital light processing 3D printing are developed with acryloyl‐modified polyethylene glycol (Acryl@PEG). The resultant photocuring inks exhibit not only high tensile strength of 14.1 MPa and elongation of 245.0%, but also excellent resilience (recover to 90.85% after 30 min under the 200% strain). With the photocuring elastomer inks, a variety of architectures including hollow vases, eggs, finger rings, and porous lattices are built with excellent precision, which all could experience large shape deformations repeatedly without any damage, indicating the excellent elasticity, outstanding shape‐recovery property, and mechanical stability. The present photocuring elastomer inks for 3D printing are therefore believed to be promising for soft robots, wearable devices, flexible electronics, and many other applications. 相似文献