Methacryloyloxy Ethyl Acetoacetate Research Articles

Surface modification of cellulose nanocrystals via SI-AGET ATRP and application in waterborne coating for removing of formaldehyde

The hazardous indoor air pollutants of formaldehyde (HCHO) are harmful for human health. Nowadays, it is important to design and fabricate green and efficient HCHO removal materials for HCHO removal from polluted indoor air. In this manuscript, cellulose nanocrystals (CNCs) as green nanomaterials were successfully surface-initiated by 2-(methacryloyloxy)ethyl acetoacetate (MEAA) as functional monomer via surface-initiated Activator Generated by Electron Transfer Atom Transfer Radical Polymerization (SI-AGET ATRP) for the application in removal of HCHO. The employment of CNCs/Poly(2-(methacryloyloxy)ethyl acetoacetate) (CNCs@PMEAA) as nanocomposites were further implanted self-healing waterborne coating for an effective way to remove HCHO. From the result, the HCHO removal efficiency reached 97.5% of CNCs@PMEAA-type coating within 300 min at room temperature, which was much higher than that of the conventional coating (82.8%). This study provides some promising green methods for designing nanocomposite's waterborne coating to remove HCHO at room temperature.

Large Area, Facile Oxide Nanofabrication via Step-and-Flash Imprint Lithography of Metal–Organic Hybrid Resins

Step-and-flash imprint lithography (S-FIL) is a wafer-scale, high-resolution nanoimprint technique capable of expansion of nanoscale patterns via serial patterning of imprint fields. While S-FIL patterning of organic resins is well known, patterning of metal-organic resins followed by calcination to form structured oxide films remains relatively unexplored. However, with calcination shrinkage, there is tremendous potential utility in easing accessibility of arbitrary nanostructures at 20 nm resolution and below. However, barriers to commercial adoption exist due to difficulties in formulating polymerizable oxide precursors with good dispensability, long shelf life, and resistance to auto-homopolymerization. Here we propose a solution to these issues in the form of a versatile resin formulation scheme that is applicable to a host of functional oxides (Al2O3, HfO2, TiO2, ZrO2, Ta2O5, and Nb2O5). This scheme utilizes a reaction of metal alkoxides with 2-(methacryloyloxy)ethyl acetoacetate (MAEAA), a polymerizable chelating agent. Formation of these inorganic coordination complexes enables remarkable resistance to auto-homopolymerization, greatly improving dispensability and shelf life, thus enabling full scale-up of this facile nanofabrication approach. Results include successively imprinted fields consisting of 100 nm linewidth gratings. Isothermal calcination of these structures resulted in corresponding shrinkage of 75-80% without loss of mechanical integrity or aspect ratio, resulting in 20 nm linewidth oxide nanostructures.

A Universal Scheme for Patterning of Oxides via Thermal Nanoimprint Lithography

AbstractDirect patterning of oxides using thermal nanoimprint lithography is performed using either the sol‐gel or methacrylate route. The sol‐gel method results in resists with long shelf‐life, but with high surface energy and a considerable amount of solvent that affects the quality of imprinting. The methacrylate route, which is limited to certain oxides, produces polymerizable resists, leading to low surface energy, but suffers from the shorter shelf‐life of precursors. By combining the benignant elements from both these routes, a universal method of direct thermal nanoimprinting of oxides is demonstrated using precursors produced by reacting an alkoxide with a polymerizable chelating agent such as 2‐(methacryloyloxy)ethyl acetoacetate (MAEAA). MAEAA possesses β‐ketoester, which results in the formation of environmentally stable, chelated alkoxide with long shelf‐life, and methacrylate groups, which provide a reactive monomer pendant for in situ copolymerization with a cross‐linker during imprinting. Polymerization leads to trapping of cations, lowering of surface energy, strengthening of imprints, which enables easy and clean demolding over 1 cm × 2 cm patterned area with ≈100% yield. Heat‐treatment of imprints gives amorphous/crystalline oxide patterns. This alliance between two routes enables the successful imprinting of numerous oxides including Al2O3, Ga2O3, In2O3, Y2O3, B2O3, TiO2, SnO2, ZrO2, GeO2, HfO2, Nb2O5, Ta2O5, V2O5, and WO3.

Synthesis of field-responsive PbTiO3 particle/polymer hybrids from metal-organics

A nanocrystalline PbTiO3 particle/polymer hybrid was synthesized through controlled polymerization and the in situ hydrolysis of metal-organics. A PbTiO3 precursor was synthesized from titanium isopropoxide, lead acetate, and 2-(methacryloyloxy)ethyl acetoacetate (MEAA). The PbTiO3 precursor was coordinated by MEAA according to nuclear magnetic resonance and infrared spectroscopy analysis. The precursor was polymerized and hydrolyzed, yielding the PbTiO3 particle/polymer hybrid. The polymer matrix was analyzed by transmission electron microscopy to include nanometer-sized crystalline particles that were confirmed to be lead titanate by electron diffraction and energy dispersive X-ray analysis. The suspension of the hybrid in silicone oil exhibited increased yield stress for an increased applied field and hybrid content. The suspension containing the synthesized hybrid showed a significantly increased yield stress compared with fluids containing PbTiO3 ceramic particles and hydrolyzed PbTiO3 precursors without MEAA modification.

Fabrication of TiO2‐Organic Hybrid Dot Arrays Using Nanosecond Laser Interference Lithography

Laser interference lithography is an established fabrication technique for periodic arrays such as photonic crystals (PCs). In this paper, we report the fabrication of a TiO2‐organic hybrid periodic array by nanosecond laser interference lithography. TiO2‐organic hybrid films were prepared from titanium tetra‐n‐butoxide and 2‐(methacryloyloxy) ethyl acetoacetate (MEAcAc) by the sol–gel method. The films were irradiated by using 10 ns pulses of 355 nm diffracted light from a Nd:yttrium–aluminum–garnet laser. The complexes formed by the Ti alkoxide and the MEAcAc were decomposed by laser irradiation, and the irradiated parts remained as periodic dot arrays on the substrate after the development. The two‐dimensional array of this TiO2‐organic hybrid material was calcined at 450°C and formed an anatase TiO2 dot array. The refractive index measured was 2.00. These dots were crack free and adherent to the substrate.

Drying and property studies on protective coatings formed by spontaneous surface polymerization

Drying studies on a protective coating formed by spontaneous polymerization on aluminum are described. The polymer coating studied here was formed from styrene, n-phenyl maleimide (NPMI), bismaleimide (BMI), and 2-(methacryloyloxy) ethyl acetoacetate (MEA). The coating successfully changed into an adherent film through drying in the presence of a coalescing solvent. Drying at a high temperature (> 170°C) enhanced the performance of the coating in terms of corrosion resistance and adhesion. It was found that the drying process involved removal of surface water on the substrate followed by formation of a dense protective layer associated with thermal crosslinking of g -diketone functional groups in the coating. The reaction mechanism, glass transition temperature, adhesion strength to aluminum, and corrosion resistance of these coatings are reported. The resultant coatings show excellent adhesion strength in a torsional test and very good resistance under the ASTM B-117 accelerated salt fog test.