CHEMICAL ENGINEERING JOURNAL
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2024
·
IF 13.3
Yutong Chen,Zhitao Yin,Yue Zhao,Zhengyang Jin,Seeram Ramakrishna,Yan Xu,Xujing Zhang
Digital Light Processing (DLP) offers the potential for personalized bone implants. Within this method, the interfacial bonding capacity of inorganic/organic materials and the solid-phase content of the slurry emerge as primary factors influencing scaffolds mechanical properties. In this research, KH571 was applied to establish an interfacial “molecular bridge”, adopting in situ coupling technology to forge stable covalent bonds between calcium silicate (CSi) and KH571. Chemical grafting, surface photografting, and photopolymerization techniques were then utilized to construct a photo-crosslinked network by CSi-KH571-TMPTA/HDDA slurry, thereby transforming the weak physical connections at the interface into strong chemical bonds. Consequently, the curing capacity and mechanical properties of the scaffolds were enhanced. Further control grain size, crystal phase transition, and shrinkage of CSi-KH571 scaffolds, post-treatment sintering processes were employed, resulting in scaffolds with a high content of β-CSi. Moreover, the optimal process parameters were selected concerning grafting rate, chemical composition, microscopic morphology, crystalline transformation, dimensional accuracy, mechanical properties, biodegradability and biocompatibility of CSi-KH571. The elastic modulus and compressive properties of CSi25-55 scaffolds exhibited a notable improvement of 29.71 % and 59.30 %, respectively, compared to CSi-50 scaffolds. By regulating the phase composition of CSi, CSi25-55 scaffolds were designed to possess a controllable degradation. In vitro cell culture experiments validated its excellent biocompatibility and promoted the proliferation and differentiation of bone marrow mesenchymal stem cells (BMSCs) as well as the deposition of bone matrix. Herein, a novel and sustainable approach has been promoted for enhancing the interfacial bonding capacity of inorganic/organic materials and the solid-phase content of printing slurry, which lays the foundation for the printing of high-resolution degradable bioceramic scaffolds.
研究领域:
材料科学
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生物医学工程
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组织工程
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增材制造
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF ADHESION AND ADHESIVES
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2019
·
IF 2.501
Zheng Su,Hua Wang,Xingyou Tian
This paper describes a facile method to control the morphology of polymer colloids and the architecture of polymer film via miniemulsion polymerization. By taking advantage of cyclization between the symmetrical diacrylate cross-linker hexamethylene diacrylate (HDDA) and the pendent vinyl in colloidal particles , the morphology of polymer colloids and the architecture of the after-formed polymer film were able to be well controlled by tuning the loading of cross-linker HDDA and crosslinking time. Four kinds of polymer colloid morphologies and four kinds of film architecture (honeycomb, close-packed, loose-packed, and enhanced-honeycomb) were characterized by TEM. The film formation mechanisms behind them were proposed based on the special and interesting results including Z-average size of the colloidal particles, Mc (molecular weight between crosslinking points) and mechanical properties of polymer film. Our results highly suggested that the morphology of polymer colloids and the polymer film architecture together determine the adhesive properties of the colloidal polymer film. The best of 180°-peel resistance, T-peel resistance and shear resistance of the polymer films were 138.12 N/25 mm, 40.98 N/25 mm and 25.72 N/cm 2 at 2.0 phm, 2.0 phm and 0.4 phm with the same crosslinking time of 90 min, respectively. The proposed method is promising to be scaled up for industrial production due to its well adaptability.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
CERAMICS INTERNATIONAL
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2016
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IF 2.758
Kehang Li,Zhe Zhao
Stereolithography (SLA) has been regarded as the most promising rapid prototype (RP) production method for ceramic parts recently because of its better precision in size and site control. The rheological behavior and curing behavior of suspensions are controlling factors for ceramic stereolithography. In this work, oleic acid (OA), stearic acid (SA) and Poly(Acrylate Ammonium) (PAA-NH 4 ) were studied as the surfactant for HDDA-based suspension formulation. Modified alumina particles exhibit different wettability with HDDA monomer and thus the different rheology behavior and stability between the formulated suspensions. OA shows the best performance among all three dispersants . 40 vol% alumina suspensions with a viscosity ˂3 Pa s at 30 s −1 shear rate were successfully formulated with OA and SA. A sintering density of 95% can be reached for the OA- and SA-modified alumina UV-curable resins.
研究领域:
材料科学
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陶瓷
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三维打印
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高分子化学
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表面化学
✓ 已验证
DOI
高影响因子
Polymer Chemistry
·
2014
·Vol. 5
·期 21
·6244-6255
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IF 5.368
Yuanyuan Xu,Youcheng Li,Xueteng Cao,Qijing Chen,Zesheng An
Reversible addition–fragmentation chain transfer (RAFT) dispersion polymerization in cononsolvents of poly(N-isopropylacrylamide) (PNIPAM) was developed as a versatile strategy for the synthesis of thermoresponsive nanogels with controlled composition, functionality and architecture. Cononsolvents composed of mixtures of methanol, ethanol and isopropanol with water were first screened for their suitability as the media for dispersion polymerization of NIPAM, and water–ethanol (75 : 25, v : v) solution was selected due to good RAFT control, efficient formation of nanogels and low toxicity. RAFT dispersion polymerization of NIPAM in the cononsolvent using poly(N,N-dimethylacrylamide) (PDMA) as the macromolecular chain transfer agent (Macro-CTA) showed good control over the molecular weight, polydispersity and pseudo linear polymerization kinetics, as characterized by gel permeation chromatography (GPC) and 1H NMR. The effect of the molecular weight of Macro-CTA, the degree of polymerization of PNIPAM, the molar ratio of [crosslinker] : [Macro-CTA] and the solid content on the formation and size of nanogels was investigated. The thermal profiles of nanogels were characterized by dynamic light scattering (DLS) both in cononsolvents and water. This cononsolvency strategy for dispersion polymerization was shown to be compatible with the incorporation of hydrophilic comonomers of N-(2-hydroxyethyl)acrylamide (HEAM) and diacetone acrylamide (DAAM). The nanogel containing DAAM was demonstrated for postpolymerization modification using ketone–alkoxyamine chemistry. More importantly, dispersion polymerization in cononsolvents allowed various hydrophobic components, e.g. butyl acrylate (BA), fluorescein O-acrylate (FLA), and 1,6-hexanediol diacrylate (HDDA), to be reliably copolymerized with NIPAM, showing well controlled polymerization, composition, nanogel size and colloidal stability. Finally, an amphiphilic block copolymer PDMA-b-PBA was used as a Macro-CTA to produce the PDMA-b-PBA-b-PNIPAM triblock copolymer and triple-layered nanogel, taking advantage of the solubility of PDMA-b-PBA and the insolubility of PNIPAM in the water–ethanol solution at the polymerization temperature.
研究领域:
高分子化学
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材料科学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）