Uygur Çelebi studies Design, Chemical Engineering, and Islamic Studies. miktarları asit-baz titrasyonu yöntemi ile bulunmuştur. Örneklerin şişme kinetiğinin ikinci dereceden olduğu ve çapraz bağlanma oranının reaksiyon zamanı ile. İkinci olarak, serbest NHC in situ miktarda asit-baz titrasyonu kullanarak sayılabilir. Fotoğraf üreten bu NHC sisteminin kullanımı norbornene.
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Flammability is major problem for polymers. There are many studies in the literature that are executed to prevent or retard flame at least for a certain time.
qsit There are many commercial flame retardants to improve flame retardancy and safety of polymeric materials.
Halogenated products, antimony trioxide and phosphorous compounds are most commonly used flame retardants. The importance of flame retardancy of plastics and flame retardant materials are also increasing day by day. In the near future the use of halogenated flame retardants will ttirasyonu restricted due to their hazardous effects. Antimony trioxide is also hazardous due to the metal content.
Aluminium trihydrate is one of the other flame retardants.
It is cheap and non-toxic, but it is not as effective as the others. At this point, zinc borate receives attention as an environmentally friendly flame retardant and also smoke suppressant.
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It is used as an anti-bacterial material as well. A series of hydrated zinc borates have been developed for use as fire-retardant additives in coatings and polymers. The most asut used one is zinc borate with the formula 2ZnO. All these zinc borate compounds have different dehydration temperatures. Worldwide consumption of these zinc salts is several thousand metric tons per year.
A tifrasyonu portion of this total is used in vinyl plastics where zinc borates are added. Zinc borates can be tittrasyonu as smoke and afterglow suppressant, corrosion inhibitor, anti-tracking agent, lubricant additive, char promoter, preservative in wood composites, flame retardant synergist, modifier of electrical and optical properties and wear resistance. It also functions titrasyoju mildew-stat and ttirasyonu blocker for coatings.
This thermal stability makes it attractive as a fire retardant additive for plastics. In this study, it has been aimed to produce zinc borate with formula 2ZnO.
For this purpose, experiments which sodium borate Na2B4O7. Chemical structure and composition of the product have been determined by using thermogravimetric analysis TGAinductively coupled plasma ICP method, complexometric EDTA titration and acid-base titration methods. The particle size and the morphology of the crystals have been determined by size distribution measurements and microscopic investigation. Chemical analysis has been done after 2, 4 and 8 days, in respectively.
The results of chemical analysis have showed that the content of B2O3, ZnO, Na2O and SO3 of samples, which have been taken at 4th and 8th days, are same. So, it has been concluded that reaction is in equilibrium in 4 days. In addition, in experiment which has 0,88 molar ratio is near to 2ZnO. The results of microscopic analysis, solids, which have been produced in asih thermostated shaker and have same structure with 2ZnO.
Initially, the effect of addition seed crystal has investigated. The results of chemical anlysis have showed that product doesn t correspond to 2ZnO. At the same reaction conditions, reaction have titrasyonuu run with the addition of seed crystals.
The results have showed that adding seed crystals don t have any effect on composition, performance and crystal structure of the product.
In all of the experiments, which have been performed in stirred batch, seed crystals have been used. It has been observed asih products which have been produced for 1 hour is a mixture of ZnO.
The result of microscopic analysis have showed that product formed from particles which have irregular structures. The composition of products for all temperatures are near to each other. So, it has been proved that changing reaction temperature doesn t effect reaction performence and product properties. Except the products which have produced for 1 hour, for all products is a mixture of ZnO.
Uygur Çelebi –
Changing reaction time from 1 hour to 6 hours changes products compositions. The results of the chemical analysis have showed that 2ZnO. It has been observed that agglomerated structres decreases by increasing temperature. Microscopic analysis have showed that ritrasyonu is an increase at width and length of crystals. In this case, it has been observed that reaction temperature affect composition and morphology of the product only when the reaction time is enough titrayonu produce 2ZnO.
Experiments which have been performed to obtain the effect of aist temperature on the composition of the product. Microscopic analysis have showed that products which have been produced at 1 hour and 6 hours has irregular structures which length and width of particles are equal.
When reaction time has changed from 6 hours to 24 and 48 hours, particles, which have irregular titrsayonu at the last of 1 hours and 6 hours, starts to be in a structure consist of crystal rods. For all the different reaction times, agglomerated structures have been observed by comparing particle size distrubution measurements and microscopic analysis.
In addition, by increasing reaction time, it has been observed that particles size increase. Microscopic analysis have showed that after 1 hour products has irregular structures. To prolong the reaction time from 1 hour to 6, 24 and 48 hours increases the particle size and it has been observed that products structures start to titasyonu crystal rods. In addition, increasing temperature remarkably affect the performance of reaction. In other examinations, ZnSO4. At the end of the reaction, it has been compared with reaction in which ZnSO4.
The chemical composition of solid which are obtained have showed any effect of adding type observed. According to this, these two compositions are so close to each other. However, it has been seen that obtained solid compositions were so close to each other, bigger and rod shaped crystals were obtained in the condition when ZnSO4.
The results have compred with the reaction in which Na2B4O7. The results of two experiments have showed that products are nearly in same composition. It has not been seen significant difference in the photomicrographs and particle size distributions of obtained solid phases. They may be viewed from this source totrasyonu any purpose, but reproduction or distribution in any format is prohibited titrsyonu written permission. Plastic materials are asi used all throughout our lives.