Microencapsulation of Styrene/Epoxydiacrylate via In Situ Polymerization of Melamine-Formaldehyde

2011 ◽  
Vol 393-395 ◽  
pp. 1279-1282
Author(s):  
Hai Ping Wang
Keyword(s):  
In Situ Polymerization ◽  
Limited Range ◽  
Thermoplastic Composites ◽  
Resonance Spectroscopy ◽  
Self Healing ◽  
Melamine Formaldehyde ◽  
Core Content ◽  
Ft Ir ◽  
And Storage

Microcapsules containing the mixture of styrene and epoxydiacrylate (St/E51-AA) for use in self-healing thermoplastic composites were synthesized by in-situ polymerization using melamine-formaldehyde (MF) as shell materials. The microcapsules were prepared in two consecutive steps, emulsification of St/E51-AA in water and then, encapsulation. The chemical structure of microcapsule was identified by Fourier transform infrared spectroscopy (FT-IR) and proton magnetic resonance spectroscopy (1H-NMR), respectively. Morphology and shell wall thickness of microcapsule were observed using scanning electron microscope (SEM). The effect of dispersion rates, through a limited range, was carefully examined on the particle size and core content of microcapsules. It was found that styrene/ epoxydiacrylate-loaded microcapsules were successfully prepared through the proposed technical route, and their mean diameters fell in the range of 36~110 μm. Both core content and microcapsule size can be adjusted by selecting different dispersion rates. The highest loading of St/E51-AA in the resultant microcapsules can be about 85%. In terms of thermogravimetric analysis (TGA), thermal behavior and storage stability of the capsules were studied.

Melamine Resin-Walled Microcapsules Containing Styrene: Preparation and Characterization

2008 ◽  
Vol 47-50 ◽  
pp. 286-289 ◽  
Author(s):  
Hai Ping Wang ◽  
Yan Chao Yuan ◽  
Min Zhi Rong ◽  
Ming Qiu Zhang
Keyword(s):  
In Situ Polymerization ◽  
Weight Ratio ◽  
Processing Parameters ◽  
Optical Microscope ◽  
Resonance Spectroscopy ◽  
Self Healing ◽  
Melamine Formaldehyde ◽  
Scanning Calorimetry ◽  
Water Emulsion ◽  
Core Content

For purposes of developing a novel self-healing chemistry for polymer composites, melamine-formaldehyde (MF) resin-walled microcapsules containing styrene were prepared by in-situ polymerization in an oil-in-water emulsion. Chemical structure of the microcapsules was identified by Fourier-transform infrared spectroscopy (FTIR) and proton magnetic resonance spectroscopy (1H NMR), respectively. In addition, scanning electron microscope (SEM) and optical microscope (OM) were used to investigate morphology and geometry of the product. The effects of dispersion rate, weight ratio of core to shell and emulsifier concentration were carefully analyzed. It was found that poly(melamine-formaldehyde) (PMF) microcapsules containing styrene were successfully synthesized through the proposed technical route, and their mean diameters fall in the range of 20~71 µm. The rough surface of the microcapsules is composed of agglomerated PMF nanoparticles. Both core content and size of the microcapsule can be adjusted by selecting different processing parameters. The highest loading of styrene in the capsules is about 60% and the emulsifier with lower molecular weight used to result in higher core content. In terms of differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), thermal behavior and storage stability of the capsules were studied. The results indicated that the microcapsules can be handled up to 72 oC.

The Preparation of Microcapsules Used for Self-Healing Composites

2011 ◽  
Vol 233-235 ◽  
pp. 2319-2322 ◽  
Author(s):  
Ru Tian ◽  
Yu Dong Zheng ◽  
Xin Liang ◽  
Zhang Ming Zhou ◽  
Xiao Li Fu ◽  
...  
Keyword(s):  
In Situ Polymerization ◽  
Ph Value ◽  
Condensation Reaction ◽  
Formaldehyde Resin ◽  
Self Healing ◽  
Mass Ratio ◽  
Melamine Formaldehyde ◽  
Stirring Rate ◽  
The Stability

Microcapsules were prepared by in situ polymerization of melamine-formaldehyde resin to form shell over oxygen resin droplets. Stirring rate, temperature, pH value as well as mass ratio of shell and core are the main parameters affecting the stability of microcapsules. High stirring rate leads to small size of microcapsules. The temperature influences the speed of the reaction and the morphology. The pH value decides whether the condensation reaction can take place. The size of microcapsules is about 15-61um.

scholarly journals Effect of Shellac Waterborne Coating Microcapsules on the Optical, Mechanical and Self-Healing Properties of Waterborne Primer on Tilia europaea L. Wood

Coatings ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 785
Author(s):  
Xiaoxing Yan ◽  
Yu Tao ◽  
Yijuan Chang
Keyword(s):  
In Situ Polymerization ◽  
Paint Film ◽  
Waterborne Coating ◽  
Preparation Process ◽  
Self Healing ◽  
Melamine Formaldehyde ◽  
Comprehensive Performance ◽  
Aging Resistance

Microcapsules of melamine formaldehyde-coated shellac and waterborne coating were prepared by in situ polymerization at 400, 600, 800 and 1000 rpm. The microcapsules prepared at four different stirring rates were added into the waterborne primer at a concentration of 5.0%, 10.0%, 15.0%, 20.0% and 25.0%. The effects of microcapsules prepared at different stirring rates and the concentration of microcapsules added into the paint film on the optical, mechanical and liquid resistance properties of the paint film were investigated. The results showed that the comprehensive performance of Tilia europaea L. waterborne primer film was the best when the concentration of microcapsules obtained at 600 rpm was 5.0%. On this basis, the aging resistance and self-healing performance of waterborne primer film on Tilia europaea L. with the best comprehensive performance were explored to lay the foundation for optimizing the preparation process of self-healing coating.

scholarly journals Microencapsulation of Liquid Cyanoacrylate via In Situ Polymerization for Self-healing Bone Cement Application – ERRATUM

2012 ◽  
Vol 1417 ◽  
pp. 1-13
Author(s):  
Vineela D. Gandham ◽  
Alice B.W. Brochu ◽  
William M. Reichert
Keyword(s):  
Bone Cement ◽  
In Situ Polymerization ◽  
Self Healing ◽  
Healing Bone

Mechanical Properties of Thermoplastic Composites via In Situ Polymerization from Cyclic Oligomers

2013 ◽  
Vol 750-752 ◽  
pp. 7-10
Author(s):  
Kou An Hao ◽  
Zhen Qing Wang ◽  
Li Min Zhou
Keyword(s):  
Mechanical Properties ◽  
In Situ Polymerization ◽  
High Viscosity ◽  
Thermoplastic Composites ◽  
Thermoplastic Matrix ◽  
Polymerization Catalyst ◽  
Short Beam ◽  
Beam Shear ◽  
Cyclic Oligomers

Fiber impregnation has been the main obstacle for thermoplastic matrix with high viscosity. This problem could be surmounted by adapting low viscous polymeric precursors Woven basalt fabric reinforced poly (butylenes terephthalate) composites were produced via in-situ polymerization at T=210°C. Before polymerization, catalyst was introduced to the reinforcement surface with different concentration. DSC is used to determine the polymerization and crystallization. SEM is used to detect whether the catalyst existed on surface. Both flexural and short-beam shear test are employed to study the corresponding mechanical properties.

Study on the Synthesis and Characterization of PANi/Nano-CeO2 Composites

2007 ◽  
Vol 124-126 ◽  
pp. 287-290 ◽  
Author(s):  
Fei Liu ◽  
Yong Jun He ◽  
Jeung Soo Huh
Keyword(s):  
In Situ Polymerization ◽  
Solid Phase ◽  
Polymerization Reaction ◽  
Solid Phase Reaction ◽  
Phase Reaction ◽  
Vis Spectroscopy ◽  
Ft Ir ◽  
Average Size

The nano-CeO2 was synthesized by two-step solid-phase reaction. The image of TEM showed that nano-CeO2 with an average size of about 70 nm. The series of polyaniline/nano-CeO2 composites with different PANi: CeO2 ratios were prepared by in-situ polymerization in the presence of hydrochloric acid (HCl) as dopant by adding nano-CeO2 into the polymerization reaction mixture of aniline. The composites obtained were characterized by FT-IR and UV-vis spectroscopy analysis. The FT-IR spectra of nanocomposites indicate different blue-shifts, attributed to C–N stretching mode for benzenoid unit. The UV-vis spectra of nanocomposites display einstein-shifts compared with PANi at 620nm. The conductivity properties of the composites are also changed compare to the pure PANi. These results suggest that the interactions between the polymer matrix and nanoparticles take place in polyaniline/nano- CeO2 composites.

scholarly journals Fabrication, Crystalline Behavior, Mechanical Property and In-Vivo Degradation of Poly(l–lactide) (PLLA)–Magnesium Oxide Whiskers (MgO) Nano Composites Prepared by In-Situ Polymerization

Polymers ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1123 ◽  
Author(s):  
Hui Liang ◽  
Yun Zhao ◽  
Jinjun Yang ◽  
Xiao Li ◽  
Xiaoxian Yang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Magnesium Oxide ◽  
Bone Repair ◽  
In Situ Polymerization ◽  
Resonance Spectroscopy ◽  
Scanning Calorimetry ◽  
Biomedical Material ◽  
In Vivo Degradation

The present work focuses on the preparation of poly(l–lactide)–magnesium oxide whiskers (PLLA–MgO) composites by the in-situ polymerization method for bone repair and implant. PLLA–MgO composites were evaluated using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and solid-state 13C and 1H nuclear magnetic resonance spectroscopy (NMR). It was found that the whiskers were uniformly dispersed in the PLLA matrix through the interfacial interaction bonding between PLLA and MgO; thereby, the MgO whisker was found to be well-distributed in the PLLA matrix, and biocomposites with excellent interface bonding were produced. Notably, the MgO whisker has an effect on the crystallization behavior and mechanical properties; moreover, the in vivo degradation of PLLA–MgO composites could also be adjusted by MgO. These results show that the whisker content of 0.5 wt % and 1.0 wt % exhibited a prominent nucleation effect for the PLLA matrix, and specifically 1.0 wt % MgO was found to benefit the enhanced mechanical properties greatly. In addition, the improvement of the degrading process of the composite illustrated that the MgO whisker can effectively regulate the degradation of the PLLA matrix as well as raise its bioactivity. Hence, these results demonstrated the promising application of PLLA–MgO composite to serve as a biomedical material for bone-related repair.

scholarly journals Preparation and Conductive and Electromagnetic Properties of Fe3O4/PANI Nanocomposite via Reverse In Situ Polymerization

2019 ◽  
Vol 2019 ◽  
pp. 1-9
Author(s):  
Di Zhang ◽  
Huaiyin Chen ◽  
Ruoyu Hong
Keyword(s):  
In Situ Polymerization ◽  
Rapid Development ◽  
Chloroform Solution ◽  
Electromagnetic Properties ◽  
Network Analyzer ◽  
The Novel ◽  
Electromagnetic Devices ◽  
Ft Ir ◽  
Polymerization Method

In this paper, the magnetite/polyaniline (PANI) nanocomposite was prepared by the novel reverse in situ polymerization method. Fe3O4 magnetic nanoparticles were synthesized in situ in PANI chloroform solution to form a suspension containing the Fe3O4/PANI nanocomposite. It overcame the disadvantage of oxidation of the Fe3O4 by the oxidant in conventional method. The Fe3O4/PANI chloroform suspension and the Fe3O4/PANI powder were characterized by FT-IR, TEM, XRD, vibrating sample magnetometer, Gouy magnetic balance, conductivity meter, and vector network analyzer. It is demonstrated that the Fe3O4/PANI suspension has a good electrical conductivity that is up to 2.135 μS/cm at the optimal ratio of reactants. The Fe3O4 nanoparticles are well dispersed in the PANI network with a particle size of about 10 nm. Fe3O4/PANI powder has high saturation magnetization and magnetic susceptibility, as well as a broad application prospect in the field of electromagnetic devices. The Fe3O4/PANI powder exhibits an excellent microwave absorption behavior, which can be an outstanding candidate for the rapid development of broadband shielding materials.

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