Method for preparing hardening agent
FIELD: rocket technique, chemical technology.
SUBSTANCE: invention relates to a method for preparing a hardening agent for polyurethane compositions based on oligodiene rubbers. Invention describes a method for preparing a hardening agent for polyurethane compositions consisting of the following components, wt.-%: oligodiene urethane prepolymer, 80-91; 20% solution of triphenylmetane triisocyanate in dichloroethane, or 27% solution of triphenylmethane triisocyanate in ethyl acetate, 7-13, and, optionally, transformer oil, 0-10. The process is carried out in the range of temperatures 55-65°C, under residual pressure 1333 Pa for 6 h. Invention provides preparing polyurethane compositions possessing the rupture strength value at the level 38 kgf/cm2, relative elongation 350-600%, elasticity modulus at 50°C at the level 41 kgf/cm2 and adhesion strength to ballistic fuel 41 kgf/cm2. Proposed compositions are able to provide working ability of articles in the range of temperature from -50°C to +50°C.
EFFECT: improved preparing method.
2 tbl, 4 ex
The present invention relates to the field of rocket technology and concerns a method for obtaining hardener for polyurethane compositions for various purposes on the basis of oligodynamic rubbers.
A method of obtaining polymeric materials with urethane groups (USSR №273424 C 08 G 22/08), taken as a prototype that could be used as an intermediate product to obtain a curing agent for polyurethane compositions used in the mountings of the products "brush" type of high-energy product. But the strict requirements laid down in the technical documentation for products of this class, which operate in the temperature range from + 50°-50°do not allow to use this material because of the high brittle temperature (TXP˜5°).
The technical task of the present invention is finding ways to obtain hardener which would have the ability to create new formulations of polyurethane compositions having stable properties, high mechanical and adhesive characteristics, and low temperature brittleness - below minus 80°C.
A technical solution is achieved through the interaction oligomannose urethane prepolymer with a content of isocyanate groups 3,0-4,0% with a 20%solution of the m aromatic triphenyltetrazolium (TFMT) in dichloroethane or 27%solution of aromatic triphenyltetrazolium (TFMT) in ethyl acetate at a temperature of 60± 5°at a residual pressure of not more than 1333 PA for 6 hours in the following ratio, wt.%:
|oligodynamic urethane prepolymer||80-91|
|20%solution of triphenyltetrazolium|
|in dichloroethane or 27%solution|
|triphenyltetrazolium in ethyl acetate||7-13|
This curing agent was prepared as follows.
In laboratory Meshaal, equipped with an anchor or frame with a stirrer, jacket heating and vacuum line, load preheated at a temperature of 60±5°With a portion oligomannose urethane prepolymer with a content of isocyanate groups in the range of 3.0 to 4.0%, a portion of transformer oil (if necessary) and a portion of a 20%aqueous solution of aromatic TFMT in dichloroethane or 27%-aqueous solution of aromatic TFMT in ethyl acetate. The synthesis is carried out at a temperature of 60±5°at a residual pressure of not more than 1333 PA for 6 hours. After a specified time Meshaal off, the mixture is cooled, make sampling to determine the content of isocyanate groups, which should be in the range of 3.5 to 4.5%.
The novelty of the offer is aemula invention is when using hardener possible to obtain polyurethane compositions with a high level of strength and highly elastic characteristics in the region of low temperatures (low temperature brittleness polyurethane compositions made using the proposed hardener, below minus 80°). The recipe oligomannose urethane prepolymer entered transformer oil and 20%solution of an aromatic TFMT in dichloroethane or 27%solution of aromatic TFMT in ethyl acetate. This hardener increased opportunities for polyurethane compositions operable in a wide temperature range of operation and increases their stability during the warranty period of storage with preservation of mechanical and adhesive characteristics, and also provides the functionality exposed to high loads.
The claimed range of ratios between the components are determined experimentally and are optimal from the point of view of formation of the polymer network, providing a high physico-mechanical adhesion and performance characteristics of the finished polyurethane composition.
In appearance the curing agent is a viscous transparent liquid from light brown to dark brown.
The prepolymer taken the La receive hardener, is a product of the interaction of Oligocene with diisocyanate.
Table 1 presents the formulation of the proposed hardener in comparison with the prototype on the application number 273424, wt.%
Recipe hardener for polyurethane compositions
|Name of the component||Prototype (molar ratio)||wt.%|
|Example 1||Example 2||Example 3||Example 4|
|1. Oligodiens: diisocyanate: unsaturated monomer||1:1,5-2,2:1,1-6,0||-||-||-||-|
|2. Oligodynamic urethane prepolymer||-||80,0||91,0||80,97||of 87.0|
|3. 20%solution TFMT in dichloroethane|
27%solution TFMT in ethyl acetate
|4. Transformer oil||-||10,0||2,0||8,1||-|
The properties of razlagaemogo hardener based oligomannose urethane prepolymer are given in table 2.
Properties hardener for polyurethane compositions
|Indices||The placeholder||Example 1||Example 2||Example 3||Example 4|
|1. The content of isocyanate groups %||not defined||the 3.8||4,0||4,3||4,5|
|2. Color||Viscous liquid from light brown to dark brown|
|3. Low temperature brittleness of hardened structures using the proposed hardener °||above minus 5||below minus 80|
|4. The viscosity at a temperature of 25°; PA·||-||41,7||40,7||41,0||40,5|
|5. Shelf life||not stored||6 months|
|Note: use of this curing agent were prepared polyurethane composition based on oligodynamic rubbers, plasticized transformer oil. The tensile strength at a temperature of 20°C at strain rate of 500 mm/min is ˜33,0-38,0 kgf/cm2that relation is sustained fashion lengthening ˜ 350-600%, a modulus at 2%elongation at a strain rate of 3.3 mm/min and at a temperature of minus 50°˜110-140 kg/cm2. The strength of adhesion to ballistic fuel is 31.5-41,0 kg/cm2with cohesion (fuel) the nature of the destruction of samples.|
From table 2 it is seen that the obtained compound is in a liquid state and has a viscosity at the level of 40.5-41.7 PA·that allows you to use it as a hardener for polyurethane compositions without special training. The hardener has a long warranty period of storage without changing its performance. Using the recommended hardener were able to achieve the lower temperature brittleness of hardened polyurethane compositions is below minus 80°S. This indicator is a basic requirement for the design of products from ballistic fuel, because the temperature range of operation of most of the charges is in the range from + 50°-50°C. the Prototype has the embrittlement temperature above minus 5°that does not meet the requirements of the design documentation.
Thus, the proposed method of obtaining a new curing agent for polyurethane compositions is achieved through the use of oligomannose urethane prepolymer in combination with 20%RA is tworoom aromatic TFMT in dichloroethane or 27%solution of aromatic TFMT in ethyl acetate plasticized transformer oil or unplasticized at a temperature of 60± 5°at a residual pressure of not more than 1333 PA for 6 hours. This hardener allows to obtain a polyurethane composition with high physical-mechanical, adhesion and performance, providing products in a wide temperature range from + 50°-50°C.
The way to obtain a curing agent for polyurethane compositions comprising oligomannose urethane prepolymer, triphenyltetrazolium and, optionally, transformer oils, namely, that interact oligomannose urethane prepolymer with a content of isocyanate groups 3,0-4,0% with 20%solution of aromatic triphenyltetrazolium in dichloroethane or 27%solution of aromatic triphenyltetrazolium in ethyl acetate, optionally in the presence of transformer oil in the temperature range 55 to 65°at a residual pressure of not more than 1333 PA for 6 h, in the following ratio, wt. %:
|Specified oligodynamic urethane prepolymer||80 - 91|
|20%solution of triphenyltetrazolium|
|in dichloroethane, or 27%solution|
|triphenyl etatisation in ethyl acetate||7 - 13|
|Transformer oil||0 - 10|
FIELD: polymer materials.
SUBSTANCE: polyurethane resin is a product of reaction of at least one diisocyanate component and isocyanate-reactive components having first group of at least one polyol, second group of at least one polyol, and third group of at least one polyol, at least one amine, and, additionally, reaction-stopping agent, all polyols of the first group having average molecular mass between 1000 and 10000 g/mole, those of second group having average molecular mass between above 10000 and 20000 g/mole, and those of third group having average molecular mass equal to or higher than 800 g/mole. Ratio of diisocyanate component to isocyanate-reactive components is selected such that all isocyanate groups are present as products of reaction with isocyanate-reactive functional groups. Resin is used as film-forming binder in coating compositions, in particular in printing inks for printing on polyolefin substrates. Printing ink is preferably used for manufacturing printed layered articles.
EFFECT: increased gluing ability and heat resistance of ink laid on plastic substrate.
41 cl, 2 tbl, 12 ex
FIELD: polyurethane composition based on oligoester polyisocyanate.
SUBSTANCE: claimed composition contains (mass parts): mixture of low molecular oligooxyethylene glycol and oligooxypropylenetriol 49.0-91.2; toluylenediisocyanate 8.0-40.5; dimethyl dichlorosilane 0.1-1.0; and low molecular polyethylene 2.5-11.5, wherein polyethylene is introduced when content of isocyanate group NCO- is achieved of predetermined value (2.0-10.5 mass %).
EFFECT: oligoester polyisocyanate with stable characteristics under long-term (up to 6 months) storage.
6 ex, 1 dwg
FIELD: method and composition for production of oligoester polyisocyanate useful as component of polyurethane compositions.
SUBSTANCE: invention relates to method for production of oligoester polyisocyanate treated with toluylenediisocyanate. Method includes controlling of NCO-group content up to predetermined value followed by addition of low molecular polyethylene. Oligoester polyisocyanate of present invention is useful as component of polyurethane compositions for production of cold cured articles.
EFFECT: reaction mass with increased viability for long storage time.
6 ex, 1 dwg
FIELD: polymers, glues.
SUBSTANCE: invention relates to thermoplastic plastics, in particular, to polyurethane and composition containing thereof used for gluing and thickening. Invention describes polyurethane prepared by interaction of: a) polyisocyanate or mixture of two or more polyisocyanates with b) polyol or mixture of two or more polyols comprising simple polyether with molecular mass 4000 Da, not less, polydispersity value 1.5, not above, or hydroxyl functionality from 1.8 to 2.0, or polydispersity value 1.5, not above, and hydroxyl functionality from 1.8 to 2.0, or by a mixture of two or more such simple polyethers in the presence of a component of the general formula (I) given in the appendix 1. After reaction termination polyurethane has at least one silane group able to react with water or its mixture with isocyanate group. Also, invention describes a composition used for thickening and gluing containing a plasticizing agent in mixture with indicated polyurethane and other polyurethane with molecular mass 8000 Da, not above, and at least by 3000 Da less as compared with this value for the first indicated polyurethane. Proposed compositions comprising the claimed polyurethane are useful as contact, single- or two-component glue, thickening mass with rupture elongation up to 287% and destroying charge up to 0.49 N/mm2 and used in sealing seams and surfaces.
EFFECT: valuable properties of composition.
15 cl, 2 ex