In Situ Polymerization of Phenolic Methylolurea in Cell Wall and Induction of Pulse–Pressure Impregnation on Green Wood

2014 ◽  
Vol 53 (23) ◽  
pp. 9721-9727 ◽  
Author(s):  
Heyu Chen ◽  
Xinwei Miao ◽  
Zifeng Feng ◽  
Junwen Pu
Keyword(s):  
Cell Wall ◽  
Pulse Pressure ◽  
In Situ Polymerization ◽  
Green Wood

In situ polymerization of 2-hydroxyethyl methacrylate (HEMA) and 3-(methacryloxy)propyltrimethoxysilane (MAPTES) in poplar cell wall to enhance its dimensional stability

Holzforschung ◽  
2019 ◽  
Vol 73 (5) ◽  
pp. 469-474 ◽  
Author(s):  
Yaoge Huang ◽  
Gaiyun Li ◽  
Fuxiang Chu
Keyword(s):  
Cell Wall ◽  
Dimensional Stability ◽  
In Situ Polymerization ◽  
Alcoholic Solution ◽  
Hydroxyethyl Methacrylate ◽  
Mass Ratio ◽  
X Ray Diffraction ◽  
Good Solubility ◽  
Modified Wood

Abstract Poplar wood samples (2×2×2 cm3) were vacuum/pressure impregnated in alcoholic solution with 2-hydroxyethyl methacrylate (HEMA) and 3-(methacryloxy)propyltrimethoxysilane (MAPTES) in a mass ratio of 3/1 in the presence of catalytic amounts of azobisisobutyronitrile (AIBN). Because of their good solubility and permeability, the HEMA/MAPTES precursors evenly penetrate the poplar cell wall. The impregnated samples were heated at 75°C for 8 h, followed by a heating period at 103±2°C for 8 h, in the course of which an in situ polymerization occurred in the cell wall. The modified wood was characterized by Fourier transform infrared (FTIR) and Raman spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Moreover, the dimensional stability of the modified wood was measured and found to be considerably improved.

In vitro and in vivo polysaccharides assembly: ultrastructural and cytochemical study of growing plant cell wall components.

1978 ◽  
Vol 36 (2) ◽  
pp. 434-435
Author(s):  
D. Reis ◽  
B. Vian ◽  
J. C. Roland
Keyword(s):  
Cell Wall ◽  
Self Assembly ◽  
Plant Cell Wall ◽  
Higher Plants ◽  
Three Dimensional ◽  
Cytochemical Study ◽  
Wall Components

Wall morphogenesis in higher plants is a problem still open to controversy. Until now the possibility of a transmembrane control and the involvement of microtubules were mostly envisaged. Self-assembly processes have been observed in the case of walls of Chlamydomonas and bacteria. Spontaneous gelling interactions between xanthan and galactomannan from Ceratonia have been analyzed very recently. The present work provides indications that some processes of spontaneous aggregation could occur in higher plants during the formation and expansion of cell wall.Observations were performed on hypocotyl of mung bean (Phaseolus aureus) for which growth characteristics and wall composition have been previously defined.In situ, the walls of actively growing cells (primary walls) show an ordered three-dimensional organization (fig. 1). The wall is typically polylamellate with multifibrillar layers alternately transverse and longitudinal. Between these layers intermediate strata exist in which the orientation of microfibrils progressively rotates. Thus a progressive change in the morphogenetic activity occurs.

Improvement in mechanical, physical and biological properties of eucalyptus and pine woods by raw pine resin in situ polymerization

2021 ◽  
Vol 166 ◽  
pp. 113495
Author(s):  
Andrey Pereira Acosta ◽  
Kelvin Techera Barbosa ◽  
Sandro Campos Amico ◽  
André Luiz Missio ◽  
Rafael de Avila Delucis ◽  
...  
Keyword(s):  
In Situ Polymerization ◽  
Biological Properties ◽  
Pine Resin

Juvenile and Mature Pinewoods Treated by in situ Polymerization with Poly(vinyl acetate)

2021 ◽  
Author(s):  
Andrey Acosta ◽  
Ezequiel Gallio ◽  
Paula Zanatta ◽  
Henrique Schulz ◽  
Rafael de Avila Delucis ◽  
...  
Keyword(s):  
Vinyl Acetate ◽  
In Situ Polymerization

scholarly journals Morphology and crystallization kinetics of Rubber-modified Nylon 6 Prepared by Anionic In-situ Polymerization

2020 ◽  
Vol 27 (1) ◽  
pp. 204-215
Author(s):  
Hongkai Zhao ◽  
Dengchao Zhang ◽  
Yingshuang Li
Keyword(s):  
Crystallization Kinetics ◽  
In Situ Polymerization ◽  
Good Description ◽  
Nylon 6 ◽  
Avrami Equation ◽  
Infrared Analysis ◽  
Chain Segment ◽  
The Impact ◽  
Kinetics Of

AbstractIn this work, we modified nylon 6 with liquid rubber by in-situ polymerization. The infrared analysis suggested that HDI urea diketone is successfully blocked by caprolactam after grafting on hydroxyl of HTPB, and the rubber-modified nylon copolymer is generated by the anionic polymerization. The impact section analysis indicated the rubber-modified nylon 6 resin exhibited an alpha crystal form.With an increase in the rubber content, nylon 6 was more likely to generate stable α crystal. Avrami equation was a good description of the non-isothermal crystallization kinetics of nylon-6 and rubber-modified nylon-6 resin. Moreover, it is found that the initial crystallization temperature of nylon-6 chain segment decreased due to the flexible rubber chain segment. n value of rubber-modified nylon-6 indicated that its growth was the coexistence of two-dimensional discoid and three-dimensional spherulite growth. Finally, the addition of the rubber accelerated the crystallization rate of nylon 6.

scholarly journals Effect of Na- and Organo-Modified Montmorillonite/Essential Oil Nanohybrids on the Kinetics of the In Situ Radical Polymerization of Styrene

Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 474
Author(s):  
Ioannis S. Tsagkalias ◽  
Alexandra Loukidi ◽  
Stella Chatzimichailidou ◽  
Constantinos E. Salmas ◽  
Aris E. Giannakas ◽  
...  
Keyword(s):  
Essential Oil ◽  
Radical Polymerization ◽  
Food Packaging ◽  
In Situ Polymerization ◽  
Average Molecular Weight ◽  
Monomer Conversion ◽  
Hydroxyl Groups ◽  
Modified Montmorillonite ◽  
Kinetics Of

The great concern about the use of hazardous additives in food packaging materials has shown the way to new bio-based materials, such as nanoclays incorporating bioactive essential oils (EO). One of the still unresolved issues is the proper incorporation of these materials into a polymeric matrix. The in situ polymerization seems to be a promising technique, not requiring high temperatures or toxic solvents. Therefore, in this study, the bulk radical polymerization of styrene was investigated in the presence of sodium montmorillonite (NaMMT) and organo-modified montmorillonite (orgMMT) including thyme (TO), oregano (OO), and basil (BO) essential oil. It was found that the hydroxyl groups present in the main ingredients of TO and OO may participate in side retardation reactions leading to lower polymerization rates (measured gravimetrically by the variation of monomer conversion with time) accompanied by higher polymer average molecular weight (measured via GPC). The use of BO did not seem to affect significantly the polymerization kinetics and polymer MWD. These results were verified from independent experiments using model compounds, thymol, carvacrol and estragol instead of the clays. Partially intercalated structures were revealed from XRD scans. The glass transition temperature (from DSC) and the thermal stability (from TGA) of the nanocomposites formed were slightly increased from 95 to 98 °C and from 435 to 445 °C, respectively. Finally, better dispersion was observed when orgMMT was added instead of NaMMT.

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