Mussel-Inspired and In Situ Polymerization-Modified Commercial Sponge for Efficient Crude Oil and Organic Solvent Adsorption

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.

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

Nanomaterials ◽

10.3390/nano11020474 ◽

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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Rapid In Situ Polymerization of Polyacrylonitrile/Graphene Oxide Nanocomposites as Precursors for High-Strength Carbon Nanofibers

ACS Applied Materials & Interfaces ◽

10.1021/acsami.1c02643 ◽

2021 ◽

Author(s):

Ye Zhang ◽

Bo Zhu ◽

Xun Cai ◽

Xiaomin Yuan ◽

Shengyao Zhao ◽

...

Keyword(s):

Graphene Oxide ◽

Carbon Nanofibers ◽

In Situ Polymerization ◽

High Strength

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Bio-based polyurethane nanocomposite thin coatings from two comparable POSS with eight same vertex groups for controlled release urea

Scientific Reports ◽

10.1038/s41598-021-89254-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Lixia Li ◽

Meng Wang ◽

Xiandong Wu ◽

Wenping Yi ◽

Qiang Xiao

Keyword(s):

In Situ Polymerization ◽

Polyhedral Oligomeric Silsesquioxanes ◽

Poly Ethylene Glycol ◽

Thin Coatings ◽

Polyurethane Coatings ◽

Coated Urea ◽

Poly Ethylene ◽

Coated Fertilizer ◽

Polyurethane Matrix

AbstractNanocomposite modification has attracted much attention in improving properties of bio-based polymer coating material for coated fertilizer. Herein two comparable polyhedral oligomeric silsesquioxanes (POSS), with eight poly(ethylene glycol) (PEG) and octaphenyl groups attached to the cage, respectively, were successfully incorporated into thin castor oil-based polyurethane coatings via in-situ polymerization on the urea surface. The nanostructure coatings are environmentally friendly, easy to prepare, and property-tunable. The results show that the vertex group of POSS had a pronounced influence on dispersion level and interaction between polyurethane and POSS that well-tuned the release pattern and period of coated urea, even at the coating rate as low as of 2 wt%. The liquid POSS with long and flexible PEG groups had better compatibility and dispersibility in polyurethane matrix than the solid POSS with rigid octaphenyl groups, as evidenced by SEM/EDS. The unique properties were resulted from the different extents of physical crosslinkings. This modification of bio-based polyurethane coating with POSS provided an alternative method of regulating and controlling the properties of coated fertilizer.

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