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For implementation of work materials of world leaders are used in industry of polymers:
- BASF;
- Huntsman;
- Bayer;
- Lankwitzer;
- DOW;
In the world there is a row of indexes which testify to the degree of developed of the state. Consumption of polyurethane - one of their. Bumper of car and corps of yacht, office and motor-car chair, sole of running shoes and knee-boot, heat-insulation of pipelines and thermo-insulation of houses - these and much other necessary the people of thing made from polyurethane foam. In 2001 years, the USA and Canada consumed 5 kg of polyuretanes per capita, Japan - 4kg, countries of ES - 4kg, Russia - 0,8kg.
Economic efficiency. As practice, use of spraying, from hard PPU allows to economize approximately 50% facilities which outlay at application of traditional methods of heat-insulation.
Polyurethane.
- polymer (elastomer), got by mixing of 2-kh components: izocianata and poliola (special mixture of polymer resins). Ordinary correlation of mixing of components of polyurethane makes 1:1 on volume or 1.1:1 on weight, can be varied depending on requirements, offered to the finished good - polyurethane, and depending on recommendation of producer of initial components (poliola and izocianata) for the receipt of polyurethane. Closeness of polyurethane approximately 1.1-1.2 kg/litre. polyurethane can be inflicted a hand method (by a roller, brush), spraying and inundation, with the use of the special equipment.
Polyurethane foam.
Made foam polyurethane. Polyurethane foam shows by itself a porous cellular structure. Hard polyurethane foam distinguish with large maintenance of the closed cell, filled gas of Z2, and elastic polyurethane foam, that has the opened cellular structure. A closeness and type of polyurethane foam can be varied in wide limits depending on initial components: from 30 to 300 kg/m3 and anymore. For sandwich panels(balanced construction), inundation of cavity, heat-insulation, hard polyurethane foam is usually used with a closeness 30-50 kg/m3. Elastic polyurethane foam in the way of life is foam rubber, details interior of cars, soles, for a shoe et cetera. Making foam of polyurethane takes place in the process of spraying or inundation. For this purpose in initial components for the receipt of polyurethane foam the special agents which make foam are entered, and/or used the special attachment, which makes foam, or pistols. Inundation of cavity of polyurethane foam and spraying of polyurethane foam on a large surface take place with the use of the special equipment.
Polyurea.
polymer (elastomer), got by mixing of 2-kh components: izocianata and polyesterimide mixture. Polyesterimides substantially dearer, than polyoly, that is why the cost of 1 kg of polymocheviny excels the cost of 1 kg of polyurethane at 4-5 one time. Correlation of mixing of components of polymochevine makes 1:1 on volume or 1.1:1 on weight. Closeness of polymocheviny approximately 1.1-1.2 kg/litre. Polymochevina is 100% by a hard matter which does not contain the gas including and volatiles, unlike polyurethane and polyurethane foam. By the choice of initial components can be got polyurea in an area from soft to hard elastomers. Introduction of dyes allows to get coverage from polyurea of necessary colors.
The hybrid system polyurethane / polyurea.
polymer (elastomer), got by mixing of 2-kh components: izocianata and mixture of polyola and polyesterimides. It is intermediate characteristics between polyurethanes and polymochevines - by high reactionary ability, by relative insensitivity to the external terms at causing, by more low price, than polyurea. Properties of the hybrid system are varied depending on maintenance of amine groups in polyola's mixture.
It is accepted to consider that at maintenance anymore 80% amine groups in polyester mix up the finished good there will be polymochevines, at maintenance less 20% amine groups in poliole the finished good will be polyurethanes, intermediate maintenance of aminnikh group in mixture (20-80%) characteristically for a hybrid polyurethane/polyurea.
Almost any thing can be purchased cheaply. But almost an always cheap analogue appears worse in quality (will remember notorious "piratic" disks). Foolishly to pay too much, but yet worse to pay too little. In last case you risk to lose everything, because the bought thing will not be able to execute the task. If you decide in behalf on cheap suggestion, you must take into account a risk to which go. And if you go to him, then you have enough money, to pay and for anything the best.
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