A polyurethane composition and the production method thereof

Abstract

The invention concerns a low-density MDI (methylene diphenyl diisocyanate) type polyether-based integral new formulation polyurethane composition and the production method of this composition, developed with alternative blowing systems to reduce the environmental impact of blowing gases already used in the polyurethane sector for use in industries such as automotive, coating, insulation. In order to achieve this purpose, the polyurethane composition of the invention contains polyol, isocyanate, cell opener and bentonite as blowing agent; and the production method of the invention comprises the steps of adjusting the weight of the polyol, adding the cell opener to the polyol and mixing it, adding bentonite to the polyol, mixing and providing homogenization, adjusting the temperature, and injection of the polyol and isocyanate into the mold.

Description

[0001] A POLYURETHANE COMPOSITION AND THE PRODUCTION METHOD THEREOF

[0002] Technical Field

[0003] The invention relates to a low-density MDI (methylene diphenyl diisocyanate) type polyether-based integral new formulation polyurethane composition developed with alternative blowing systems to reduce the environmental impact of blowing gases already used in the polyurethane sector for use in industries such as automotive, coating, insulation and the production method of this composition.

[0004] Prior Art

[0005] Nowadays, blowing agents are used in the polyurethane industry. However, these gases used as blowing agents have adverse effects on the environment. For this reason, restrictions have been imposed on the use of these gases with the regulations.

[0006] The gases used in the current technique are removed after the usage period of 5-10 years due to regulations. For this reason, long-term and environmentally friendly systems have been sought in the polyurethane sector, which are advantageous in terms of cost independent of regulations. In the current technique, bentonite clay is used as an additive with other chemical materials in polyurethane systems. On the other hand, no studies have been found in which it is used as blowing agent in polyurethane parts produced for use in the automotive sector. As a result, developments on the subject are needed.

[0007] In the literature, application numbered TR 2007 / 06276 and titled "Polyurethane liquid membrane insulation and isolation material" has been found. The said invention relates to a polyurethane liquid membrane insulation and isolation material containing 65% castor oil (main resin), isocyanate (hardener), anti-precipitation component, lubricant agent and UV resistance mixture, 15% fiberglass, 8% bentonite, 2% aluminum silicate and 10% talc-calcite anti-leakage. The mentioned mixture contains 65% castor oil (main resin), 30% isocyanate (hardener), 1.5% anti-collapse component, 3% lubricant agent, and 1% UV resistance. The use of bentonite in the production of polyurethane is mentioned in this document. However, there is no mention here of the use of bentonite as an blowing agent or its use individually. It also does not contain polyol. In addition, the product here is in liquid form and there is no mention of a molding process here. For all these reasons, it is thought that the subject of our invention contains innovation in comparison to this document.

[0008] In the literature, the application numbered WO 2012123253 A2 has also been found. This invention relates to a method for estimating the effects of nano components on the hygienic-chemical properties of polymeric materials and thus producing new improved polymeric compositions is described. In this invention, bentonite is used in order to increase the sanitary and hygienic properties of the material, and the use of bentonite as an blowing agent is not mentioned. Also, the use of different metallic materials in addition to bentonite is mentioned here. For all these reasons, the product and method here are different from our invention.

[0009] As a result, due to the above-mentioned problems and the inadequacy of the existing solutions, it has been necessary to make a development in the technical field.

[0010] Brief Description of the Invention

[0011] The present invention relates to a polyurethane composition and its production method that meets the above-mentioned requirements, eliminates all disadvantages and brings some additional advantages.

[0012] The primary purpose of the invention is to develop a polyurethane composition and production method by using bentonite clay in natural mineral structure as an blowing agent, which has no adverse effects on the environment and has a low cost.

[0013] Another purpose of the invention is to develop a polyurethane composition and its production method, which enables to obtain low-density polyurethane material by maintaining the desired physical and mechanical properties.

[0014] A purpose of the invention is to develop a polyurethane composition and its production method, which allows the product to be used in lower densities than the amount of bentonite clay used, without impairing the skin quality and acoustic performance of the product.

[0015] In order to achieve all of the purposes described above, the invention In order to fulfill the above-described purposes, the invention is the polyurethane composition comprise polyol, isocyanate, cell opening and bentonite as blowing agent; and the production method comprises the steps of adjusting the weight of the polyol, adding the cell opener to the polyol and mixing, adding bentonite to the polyol, providing mixing and homogenization, adjusting the temperature, and injection of the polyol and isocyanate into the mold.

[0016] The structural and characteristic features and all advantages of the invention outlined in the detailed description below will be understood clearly, therefore the evaluation should be made by taking the detailed explanation into consideration.

[0017] Detailed Description of the Invention

[0018] In this detailed description, a polyurethane composition of the invention and its production method will be explained only for a better understanding of the subject matter and without any restrictive effect.

[0019] The invention basically consists of polyether-based polyol, MDI isocyanate (methylene diphenyl diisocyanate), bentonite clay and cell opener. The usable and preferred quantity by weight of the components used in the invention are presented in Table 1 as percentages.

[0020] Table 1. Percentages by weight of the components of the invention

[0021] Bentonite is used as an blowing agent in the invention. The cell opener, on the other hand, is used to adjust the cell and pore structure. Thus, acoustic expectations are met in accordance with how it is desired, because the open or closed pore structure directly affects the acoustic performance. In addition, the hardness of the part and the skin formation of the part are adjusted by changing the MDI isocyanate ratio. In the current technique, blowing can be provided by using C3H8O2, C3H3F5 gases or C2H402(Ecomate®) instead of bentonite. However, these blowing agents have harmful effects on the environment. Although water and CO2 gas are also used as blowing agents in the current technique, excessive use of them causes structural defects in the material. For these reasons, bentonite clay, which is more environmentally friendly, is used as an blowing agent in the invention instead of these chemicals in the technique.

[0022] In order to obtain the polyurethane composition, the production method of the invention basically includes the steps of adjusting the weight of the polyol, adding the cell opener to the polyol and mixing, adding bentonite to the polyol, mixing and providing homogenization, adjusting the temperature, injection of polyol and isocyanate into the mold.

[0023] In the method of the invention, firstly, the weight adjustment of the polyol is performed in the mixing tank. Here, the temperature is in the range of 23-30<C, preferably 23<C. Then, cell opener is added to the polyol at the rates specified in Table 1 and mixed for 10 minutes. Then bentonite is added to the mixture and the mixture is mixed for another 20 minutes. In this step, bentonite must be added to the polyol via a helix system. Otherwise, homogenization cannot be achieved in the mixture. In this case, bentonite can cause local agglomerations in polyol. This, in turn, causes uneven blowing in all parts of the molded material, mixing problems (due to nozzle clogging) and production of defective products. In short, it is important to ensure homogenization here. After homogenization, the temperature of the resulting mixture is measured, preferably with the help of a thermocouple. Here it is necessary to confirm that the temperature is in the range of 23-30 <0, preferably 23 <0. Following that , the polyol mixture and MDI isocyanate are injected into the mold with pressure using the injection molding method. The pressure applied in this step is in the range of 130-170 Pa, preferably 160 Pa. Finally, the material is kept in the mold and the reaction is completed. The waiting time here is around 220-280 seconds, preferably 4 minutes. By opening the mold, the polyurethane part produced in accordance with the method of the invention is obtained.

[0024] With the product developed by the invention, vibration dampening on and around the engine, especially in internal combustion vehicles, ensures that the engine noise is less in the vehicle. In accordance with the regulations, gases are changed with certain periods because they harm nature. Using bentonite, a sustainable production is provided for a long time without any process change required. The flammable and explosive properties of the blowing agents have been eliminated from the system; because there is no such flammable effect for bentonite.

Claims

CLAIMS1. A polyurethane composition comprising polyol, isocyanate and cell opener, characterized by comprising; the bentonite as an blowing agent.

2. The polyurethane composition according to Claim 1 , characterized by comprising; a polyether-based polyol in the range of 49-70%, MDI isocyanate in the range of 28-40%, bentonite in the range of 1 -30% and cell opener in the range of 0.03-1 % by weight.

3. The polyurethane composition according to Claim 1 , characterized by comprising; 59.344% of polyether based polyol, 37.5% of MDI isocyanate, 3.125% of bentonite and 0.031% of cell opener by weight.

4. A production method for a polyurethane composition according to claims above, comprising process steps of• The adjustment of polyol weight (a),• Adding the cell opener to the polyol and mixing it (b),• The adjustment of the temperature (d),• The injection of polyol and isocyanate into the mold (e), characterized by comprising adding bentonite to the polyol, mixing and homogenization (c) processes between the steps “b” and “d.”5. The production method according to Claim 4, characterized in that; the temperature is in the range of 23-30 <C at the proc ess steps "a" or "d."6. The production method according to Claim 4, characterized in that; the temperature is 23 <C at the process steps "a" or "d ."7. The production method according to Claim 4, characterized in that; the mixing period in the process step "b" is 10 minutes.

8. The production method according to Claim 4, characterized in that; the mixing period in the process step "c" is 20 minutes.The production method according to Claim 4, characterized by comprising; the process of adding bentonite to polyol with helix system to ensure homogenization. The production method according to Claim 4, characterized in that; in the step "e", in the mold injection process, the pressure is between 130-170 Pa and the holding time in the mold is between 220-280 seconds. The production method according to Claim 4, characterized in that; in the step "e", in the mold injection process, the pressure is 160 Pa and the holding time in the mold is 4 minutes.

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