The Polarity of poly(methyl methacrylate) Copolymers

2014 ◽  
Vol 687-691 ◽  
pp. 4411-4414 ◽  
Author(s):  
Yan Hong Zhang ◽  
Yan Wang ◽  
Xian Chao Kong ◽  
Dong Mei Zhao

Poly (methyl methacrylate) (PMMA) is known as one of the common transparent polymer materials. In this work, pure poly (methyl methacrylate), methyl methacrylate-acrylonitrile copolymer, methyl methacrylate-styrene copolymer was synthesized by bulk polymerization based on the mechanism of free radical polymerization to observe the polarity change of the PMMA after introducing styrene and acrylonitrile monomers. Meanwhile the glass transition temperature, hardness, contact angle and color distribution of the copolymer were measured through polymer temperature deformation analysis experiment, hardness and contact angle measuring instrument.

1997 ◽  
Vol 501 ◽  
Author(s):  
Naohisa Yanagihara ◽  
Kazutaka Uchida ◽  
Muyuki Wakabayashi ◽  
Toru Hara

ABSTRACTSolid sol of silver in poly(methyl methacrylate), Ag/PMMA, was prepared by bulk polymerization of methyl methacrylate solution of silver (I) triflluoroacetate (AgTfa) and followed by postheating. The formation of the metallic Ag nanocluster was characterized by visible spectroscopy, and effects of the concentrations of AIBN and AgTfa and the heat-treatment duration on the formation of Ag cluster were investigated. Furthermore, based on the kinetic study of MMA in the presence of AgTfa, possible mechanism for the reduction and agglomeration of silver is proposed.


Langmuir ◽  
1990 ◽  
Vol 6 (2) ◽  
pp. 420-424 ◽  
Author(s):  
D. Briggs ◽  
H. Chan ◽  
M. J. Hearn ◽  
D. I. McBriar ◽  
H. S. Munro

2019 ◽  
Vol 2019 ◽  
pp. 1-12
Author(s):  
Matthias Katschnig ◽  
Boris Maroh ◽  
Natascha Andraschek ◽  
Sandra Schlögl ◽  
Ulrike Zefferer ◽  
...  

Whilst the significance of substrate topography as a regulator of cell function is well established, a systematic analysis of the principles underlying this is still unavailable. Here we evaluate the hypothesis that surface energy plays a decisive role in substrate-mediated modulation of cell phenotype by evaluation of cell behaviour on synthetic microstructures exhibiting pronounced differences in surface energy. These microstructures, specifically cubes and walls, were fabricated from a biocompatible base polymer, poly(methyl methacrylate), by variotherm injection molding. The dimensions of the cubes were 1 μm x 1 μm x 1 μm (height x width x length) with a periodicity of 1:1 and 1:5 and the dimensions of the walls 1 μm x 1 μm x 15 mm (height x width x length) with a periodicity of 1:1 and 1:5. Mold inserts were made by lithography and electroplating. The surface energy of the resultant microstructures was determined by static contact angle measurements. Light scanning microscopy of the morphology of NT2/D1 and MC3T3-E1 preosteoblast cells cultured on structured PMMA samples in both cases revealed a profound surface energy dependence. “Walls” appeared to promote significant cell elongation, whilst a lack of cell adhesion was observed on “cubes” with the lowest periodicity. Contact angle measurements on walls revealed enhanced surface energy anisotropy (55 mN/m max., 10 mN/m min.) causing a lengthwise spreading of the test liquid droplet, similar to cell elongation. Surface energy measurements for cubes revealed increased isotropic hydrophobicity (87° max., H2O). A critical water contact angle of ≤ 80° appears to be necessary for adequate cell adhesion. A “switch” for cell adhesion and subsequently cell growth could therefore be applied by, for example, adjusting the periodicity of hydrophobic structures. In summary cell elongation on walls and a critical surface energy level for cell adhesion could be produced for NT2/D1 and MC3T3-E1 cells by symmetrical and asymmetrical energy barrier levels. We, furthermore, propose a water-drop model providing a common physicochemical cause regarding similar cell/droplet geometries and cell adhesion on the investigated microstructures.


2012 ◽  
Vol 557-559 ◽  
pp. 304-308 ◽  
Author(s):  
Chun Bao Zhao ◽  
Xin Wang ◽  
Xu Jie Yang ◽  
Wei Zhao

A series of poly(methyl methacrylate) (PMMA) composites containing polyhedral oligomeric silsesquioxane (POSS) were produced by bulk polymerization. The morphology, thermal and mechanical properties of the composites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), thermogravimetric analyses (TGA) and dynamic mechanical analyses (DMA). Results show that the octa(3-chloropropyl)-POSS (ocp-POSS) and trisilanolphenyl-POSS (triol-POSS) have high compatibility with PMMA and can be uniformly dispersed into PMMA matrix. The separate incorporation of these two types of POSS contributes to the improvement of thermal stability of PMMA composites. When the content of POSS was 7.5 wt%, the thermal decomposition temperatures (5% mass loss) of PMMA composites with ocp-POSS and triol-POSS were increased by about 104 °C and 130 °C, respectively. The increase of triol-POSS content in the PMMA matrix gave slight enhanced storage modulus before glass transition.


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