Low temperature plasma treatment

An ultrathin layer of plasma polymer of trimethylsilane (TMS) has been utilized in the corrosion protection of aluminum alloys by means of system approach interface engineering (SAIE) [1 ]. SAIE by means of low-temperature plasmas utilizes low-temperature plasma treatment and the deposition of a nanolilm by luminous chemical vapor deposition (LCVD). This approach does not rely on the electrochemical corrosion-protective agents such as six-valence chromium, and hence the process is totally environmentally benign. 

Cokes prepared from coal by low-temperature plasma treatment have larger surface area than those prepared by normal or rapid heating226. ... 

In recent investigations, a great deal of attention has been paid to low temperature plasma treatment. However, there are problems, for example, the effectiveness of the treated surfaces possibly degrades with time Therefore, it is said that the low temperature plasma treatment is not a permanent treatment. 

In this study, in order to improve the adhesion properties of aramid fibers to rubber as matrix, nylon thin films were securely formed on the surfaces of the aramid fibers by a radio frequency ion-plating (RFIP) method which represents an application of low temperature plasma treatment. These fibers were coated with a RFL (resorcinol-formaldehyde-latcx) adhesive which has high affinity to both nylon and rubber The adhesion properties of the fibers to rubber were evaluated, and the effects of the RFIP method were confirmed by a comparison of the RFIP treated fibers with those subjected to the low temperature plasma treatment. The usefulness of such surface modification methods will be discussed. 

For low temperature plasma treatment, the aramid fabric samples were treated for predetermined times using a bell jar type RF ion-plating apparatus, as shown in Figure 2, at a ftequency of 13,56 MHz (inside diameter 500mm, height=600mm, manufactured by Sanritsu Seisakusho Co.) at a discharge output... 

Adhesion Properties For the purpose of improving the adhesion properties to resins, various types of low temperature plasma treatments have been investigatedHowever, only a few reports on the improvement of adhesion properties to rubbers were found. ... 

In comparison, Technora woven fabric samples had higher adhesion properties (peel strength, rubber coverage) than the PPTA fabric samples. The reason, while not completely understood, may lie in the fact that Technora has a chemical structure which is more easily activated by the low temperature plasma treatment as compared with that of PPTA. In the case of PPTA, fibrils are more readily formed as compared with Technora which is a copolymer, and also weak boundary layers are produced by the low temperature plasma treatment. 

Comparison with Plasma Treatment. Under the experimental conditions employed in this study, the adhesion properties obtained through the deposition of the nylon thin films were higher than those obtained via the low temperature plasma treatment, as shown in Figure 8. It is presumed that the small difference in the adhesion properties between the low temperature plasma treatment and nylon-RFIP method can be attributed to the coating with RFL adhesive immediately after the low temperature plasma treatment which is accompanied by time-... 

Figure 8, Comparison of peel strength between plasma treated and nylon ion-plated Technora fabric samples coated with RFL to rubber. Conditions of low temperature plasma treatment and RFIP method 10 torr., 5 min. for plasma treatment and 10 min. for RFIP.

Comparison Between Technora and PPTA. In this study, dealing mainly with Technora , it was also confirmed that the PPTA shows almost the same behavior as Technora except for a difference in the adhesion level, as shown in Figures 10 and 11. More particularly, not only in the case of the low temperature plasma treatment but also for the RFIP method of the nylons, the adhesion properties of Technora bric samples wore higher than those of PPTA fabric samples. As a IHobable reason for this behavior, the reactivities of nylon thin films with the RFL adhesive in both fibers are estimated to be equal, and it is assumed that the adhesion properties of the nylon thin films to the Technora fabric samples are higher than those to PPTA fabric samples. 

Conditions of low temperature plasma treatment and RFIP method 10 torr. 5 min. for plasma treatment and 10 min. firrRFIP. 

It is shown that the adhesion properties of rubbers can be enhanced by low temperature plasma treatment of the aramid fibers with inactive surfaces, and coating with RFL adhesive immediately after the treatment. 

Antistatic treatment Kan (2007) studied the effect of discharge power of a low-temperature plasma treatment on the antistatic property of polyester fabric. The results reveal that when the discharge power increases, the half-hfe decay time decreases accordingly, which means that a better antistatic property is achieved. When... 

Figure 3.12 Effect of system pressure of low-temperature plasma treatment on the antistatic property of polyester fabric (Kan, 2007a).

Mertens, N., et al. Low temperature plasma treatment of human tissue. In 2nd International Conference on Plasma Medicine, San Antonio, TX, USA (2009)... 

Steen, M.L., Hymas, L., Havey, E.D., Capps, N.E., Castner, D.G. and Fisher, E.R. 2001. Low temperature plasma treatment of asymmetric polysulfone membranes for permanent hydrophilic surface modification, 188(1) 97-114. 

Kang, M.S., Chun, B. and Kim, S.S. 2001. Surface modification of polypropylene membrane by low-temperature plasma treatment. 

Qi, K., Xin, J. H., Daoud, W. A. and Mak, C. L. 2007. Functionalizing polyester fiber with a self-cleaning property using Anatase Ti02 and low-temperature plasma treatment. IntemationalJoumal of Applied Ceramic Technology, 4, 554-63. 

Kan C W (2001), The Effect of Low Temperature Plasma Treatment on Different Types of Wool Eibre The 6th Asian Textile Conference, Innovation Globalization, Proceedings, August 22-24, Hong Kong. 

Low-temperature plasma treatment is an important means to achieve these objectives without alteration of the bulk properties and without the use of solvents or reagents to be removed later in the process [ 101,102]. Plasma etching with non-polymerizable gases Uke argon, nitrogen or sulfur dioxide, was introduced to hydrophilization and fimctionalization [ 103]. The plasma-induced graftcopo-lymerization of monomers with suitable functional groups can be appUed for subsequent immobiUzation reactions. 

Powders are commonly used as fillers for rubber mixes. The most popular are carbon black, silica, kaolin, or more modem like graphene, fullerenes and carbon nanotubes. The nature of their surface is the main attribute of fillers, as surface energy and specific area determine the compatibility of filler with mbber matrix and the affinity to other c ingredients. One of the major problems is the tendency of fillers to agglomeration - formation of bigger secondary stmctures, associated with lower level of filler dispersion, what is reflected by the decrease of mechanical properties of mbber vulcanizates [1]. Surface modification of powder can improve interaction between mbber matrix and filler. Application of low-temperature plasma treatment for this purpose has been drown increasing attention recently [2, 3]. 

For example, the low-temperature plasma treatment is a technique that does not negatively affect the environment, so that it is widely applied for modifying the polymer substrate surface. The main benefits of this technique are (Kim et al. 2005) ... 

Due to thermal effects the pyrolysis of the Co-TMPP precursor leads to destruction of the N -centers and melting of the metallic centers. Thereby, the particle sizes grow rather large, which prevents the preparation of catalyst layers by means of spraying techniques. Improvements have been achieved by means of low temperature plasma treatment of the prectusor structures. The carbonization of the porphyrin structure is achieved by electrical energy instead of pyrolysis. The particle size distribution is shifted towards smaller particles compared to that obtained by pyrolysis of the TMPP precursor (see Fig. 3.4). >... 

Fig. 8. Plot showing the wear rate of UHMWPE exposed to a range of low temperature plasma treatments [99]...

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