Optimizing electric corona treatment for hydroxypropylated starch-based coatings

The effect of various corona treatments of cotton card sliver on yarn and fabric properties and on spinning performance has been investigated. The corona increased yarn strength, especially at low twist levels and for coarse counts, without adversely affecting yarn evenness. At a given twist the corona treatment gave less end-breaks than untreated cotton. It also increased fabric strength but harshened fabric hand, both before and after wet finishing.

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High Oxygen Barrier Polyethylene Films

Polymers and Polymer Composites ◽

10.1177/096739111702500802 ◽

2017 ◽

Vol 25 (8) ◽

pp. 571-582 ◽

Cited By ~ 1

Author(s):

Carmen Fernández Ayuso ◽

Alejandro Arribas Agüero ◽

Jose A. Plaza Hernández ◽

Antonio Bódalo Santoyo ◽

Elisa Gómez Gómez

Keyword(s):

Food Packaging ◽

High Oxygen ◽

Oxygen Barrier ◽

Layer By Layer ◽

Insulating Layer ◽

Polyethylene Films ◽

Barrier Films ◽

Film Substrate ◽

Corona Treatment ◽

Thermal Stability Of

“Layer by layer” technology was used to create transparent, thin and high barrier polyethylene films to use in food packaging. These films were made by inserting successive layers of polyacrylamide and montmorillonite (Cloisite Na+, non-organic modification) grown onto a low density polyethylene (LDPE) film substrate submitted to corona treatment. Excellent oxygen permeability results were reached with only 9 bilayers, with a reduction of 99.92%, compared to the pure polyethylene. This allowed the oxygen barrier film to change from poor to high (3.66 cm3/m2·day), with a total thickness of 48 microns, due to the structure formed over the film to create a tortuous path for oxygen molecules. Optical properties were analysed, showing a ≥92% transparency in all samples. Thermal stability of polyethylene was slightly improved and this was attributed to nanoclays presence forming an insulating layer. The result of this research is a thin structured film which is a good candidate for common barrier films replacement in food packaging thanks to its high oxygen barrier capacity, optical transparency, microwaveability and recyclability.

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Corona Treatment of Filled Dual-polymer Dispersion Coatings: Surface Properties and Grease Resistance

Polymers and Polymer Composites ◽

10.1177/096739111702500402 ◽

2017 ◽

Vol 25 (4) ◽

pp. 257-266 ◽

Cited By ~ 2

Author(s):

Sami-Seppo Ovaska ◽

Pavel Geydt ◽

Ringaudas Rinkunas ◽

Tadeusz Lozovski ◽

Robertas Maldzius ◽

...

Keyword(s):

Surface Energy ◽

Direct Current ◽

Photoelectron Spectroscopy ◽

Rapeseed Oil ◽

Surface Composition ◽

Surface Elasticity ◽

Contact Angles ◽

Treatment Unit ◽

Barrier Coating ◽

Corona Treatment

Dispersion coating layers consisting of hydroxypropylated starch, 0–30 pph of barrier-grade talc and 0–10 pph of styrene-butadiene latex were subjected to both positive and negative direct-current corona treatments utilizing a specially developed dynamic treatment unit. The effects of the surface composition (barrier coating) on the response to the direct current corona treatment were evaluated by measuring contact angles and determining the surface energy. The effects of corona treatment on the properties of the barrier coating were further determined by measuring the contact angle of rapeseed oil and the grease resistance. It was found that the grease resistance of the corona-treated barrier coatings was substantially lower than that of untreated samples, which was ascribed to holes caused by corona discharge strike-through and to chemical changes on the treated surfaces. The corona treatment lowered the surface energy of the coatings, as indicated by an increase in the contact angles of water and rapeseed oil. Changes in the dispersion part of the surface energy were recorded, particularly after positive treatment voltage, whereas a negative discharge led to greater changes in the polar part of the surface energy. X-ray photoelectron spectroscopy (XPS) tests revealed an increase in the proportion of talc at the surface after corona treatment, which indicates a migration caused by the applied electric field. The peak force tapping mode of an atomic force microscope revealed moderate topographical changes in the coatings and a decrease in surface elasticity, supporting the migration of talc particles. In addition, significant changes in the physicochemical properties of the untreated reverse side were observed.

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Computation of Power Released During Corona Treatment on Polymeric Insulators Under Ac and Dc Excitation

Energy Procedia ◽

10.1016/j.egypro.2015.07.380 ◽

2015 ◽

Vol 75 ◽

pp. 2205-2210

Author(s):

Subba Reddy B ◽

Shakthi Prasad D

Keyword(s):

Polymeric Insulators ◽

Dc Excitation ◽

Corona Treatment

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Mechanism of corona treatment on polyolefin films

Polymer Engineering & Science ◽

10.1002/pen.10264 ◽

1998 ◽

Vol 38 (6) ◽

pp. 965-970 ◽

Cited By ~ 56

Author(s):

Dong Zhang ◽

Qin Sun ◽

Larry C. Wadsworth

Keyword(s):

Corona Treatment

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Application of corona treatment to modify the surface layer of textile polimer materials. Analysis of the issue, design of equipment, and preliminary studies

Polimery ◽

10.14314/polimery.2009.421 ◽

2009 ◽

Vol 54 (06) ◽

pp. 421-429 ◽

Cited By ~ 5

Author(s):

STEFAN BRZEZINSKI ◽

MARIAN ZENKIEWICZ ◽

STEFAN POLOWINSKi ◽

DOROTA KOWALCZYK ◽

IWONA KARBOWNIK ◽

...

Keyword(s):

Surface Layer ◽

Materials Analysis ◽

Corona Treatment

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Effects of Different Treatments on Surface Activity of Rice Straw Particleboard

Science of Advanced Materials ◽

10.1166/sam.2020.3528 ◽

2020 ◽

Vol 12 (2) ◽

pp. 289-295 ◽

Cited By ~ 4

Author(s):

Xian-Qing Xiong ◽

Ying-Ying Yuan ◽

Yi-Ting Niu ◽

Liang-Ting Zhang ◽

Zhi-Hui Wu

Keyword(s):

Rice Straw ◽

Surface Activity ◽

Treatment Time ◽

Ph Value ◽

Sodium Hydroxide Solution ◽

Alkali Treatment ◽

Surface Absorption ◽

Bonding Performance ◽

Absorption Performance ◽

Corona Treatment

The surface activity of rice straw particleboard (RSP), which has a significant effect on the finishing and bonding performance, is reduced by wax coating and free radicals on the straw fiber. The RSP surface was treated by corona treatment and alkali treatment to reveal the effects of different treatments on the surface activity of RSP. The infiltration height method was applied to evaluate the variation of surface activity. The alkalized samples of RSP with different densities were prepared by using sodium hydroxide solution with pH value of 8∼14. The samples of different densities were then subjected to corona treatment under high purity oxygen conditions with treatment power of 50 W, 100 W, 300 W, and 500 W and with a time of 4 min or 7 min. The surface activity of the treated specimens was evaluated by measuring the absorption properties of three kinds of liquids by infiltration-height method: distilled water, glycerin, and alcohol. The results revealed the following. (1) After alkalization treatment, the surface absorption performance of RSP for these three liquids was improved, and it increased with the increase of pH value of the treatment solution. The suitable pH value of the alkalized solution for RSP is 7∼11, which can improve the surface absorption performance. (2) After corona treatment, the surface absorption performance of RSP increased with the increase of corona treatment power. RSP had the highest surface absorption performance for alcohol. With the density of RSP increased, the surface absorbability slightly decreased. Therefore, it is not suitable to utilize corona treatment in improving absorption for the higher density RSP. At the same time, with the variation of corona treatment time, the absorption of RSP surface changed irregularly because of the polarity of different test liquids. (3) The reasonable parameters of alkalization treatment and corona treatment are beneficial in improving the gluability of RSP. These results have guiding significance for RSP surface decoration process.

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