CS213339B2 - Method of making the liquid heat isolating means against ageing the shaped polykapronamide products - Google Patents

Description

The invention relates to a process for the production of a liquid, heat-stable anti-aging composition, in particular in the form of a liquid solution or concentrate, increasing the resistance of shaped polycaponamide products to prolonged exposure to higher temperatures in the range of 120 to 220 ° C and to exposure to ultraviolet radiation in the presence of atmospheric oxygen.

The high molecular weight poly-s-capronamide containing the anti-aging agent produced by the process of the present invention can be melt molded by known processes for manufacturing machine parts, fibers, films, laminates and technical articles or other shaped articles, including reinforced, characterized by improved utility features and extended life.

Molded polyamide products such as fibers, foils and technical molded articles made from linear high molecular weight poly-e-capronamide or other aliphatic polyamides are characterized by insufficient resistance to higher temperature and light, i.e. low resistance to chemical destructive agents in the presence of atmospheric oxygen at higher temperatures and ultraviolet radiation, resulting in their premature aging and degradation under working conditions.

Various anti-aging chemicals, in particular complex copper compounds containing Cu ²⁺ cations, are used to increase performance and to extend the life of molded polyamide articles. Compositions of this type suitable for stabilizing polyamide products in the mass against heat and light are obtained by reacting hydrated copper compounds with organic compounds whose molecules or ions contain at least one oxygen and / or nitrogen and / or sulfur atom.

In accordance with the foregoing, Japanese Patent Specifications Nos. 7,697/73, 7,698/73, 7,700/73, 20,017/73, and British Patent Specification No. 1,297,538 disclose processes in which chloride is cuprous CU2CI2 or CuCl ₂ is reacted with aromatic diamines, or - according to the methods described in Japanese patent Nos. 48-7 and 8 737/73 858/73 - let heterocyclic compound having midazolovou Benzi, benzothiazole, 2-mercaptobenzimidazole or 2-mercaptobenzthiazole structure, react with copper (I) chloride or iodide, optionally with mixtures of potassium iodide with copper (I) iodide or potassium iodide with copper (I) chloride to form blue crystalline powder products (VR Koroleva et al., Chimicheskije volokna, 1976, 3, p. 22) .

Similarly, Japanese Patent Specification No. 28,661/74 discloses a process for preparing complex copper compounds by reacting 8-mercaptoquinoline or a halogen derivative thereof with an aqueous solution of copper acetate. US Patent Nos. 170,672 and 235,906 and Japanese Patent No. 9,750/72 disclose high molecular weight thermal stabilizers in the form of blue-green powdered products obtained by reaction of copper acetate with carbon chain copolymers having free carboxyl groups ; these copolymers are obtained by copolymerizing ethylene with maleic acid and acrylic or methacrylic acid with their methyl esters. Similarly, by reaction of cuprous acetate or cuprous chloride with macro-heterocyclic compounds containing isoindole or naphthoisoindole residues, for example, thiadiazoleindole, thiadiazoleindophenylene, 2-mercapto-3-iminomethylbenzo (b) thiophene,,, Ν'-bis [2-mercapto] (b) thenylidene] ethylenediamine or 2-mercapto-3-benzo (b with thiophenaldehyde) to provide complex compounds of the copper phthalocyanine type in the form of brown-black powdered products (US Pat. Nos. 246,834, 263,136 and 322,349; RP Smirnov: Izvěstija College the introduction of the USSR, Khimija and Chemical Technology, 1964, Vol. 17, p. 118; 1967, Vol. 10, p. 1262; stabilizers against the effects of higher temperatures and against the effects of light on the basis of complex copper compounds is that they are carried out in several stages, that their industrial rea use of hardly accessible and expensive organic intermediates as well as special equipment. Another disadvantage is the relatively low repeatability of the synthesis processes, resulting in unsatisfactory yields and unsatisfactory quality of the products obtained.

Technological difficulties with the use of specific inhibitors for stabilizing polyamide products are that they undergo chemical decomposition in the reducing environment of caprolactam polymerization at 270 ° C or in contact with a polyamide melt at a temperature in the range 290 to 305 ° C to form copper salt or cuprous oxide. , which are the source of difficult-to-remove clusters, deteriorating the processing properties of the polyamide and undesirably coloring the polymer and articles thereof.

Also, numerous organic copper derivatives and mixtures thereof with other substances, such as iodine compounds, have a negative, uncontrolled effect on the kinetics of the caprolactam hydrolytic polymerization process, which makes it difficult to obtain fiber-forming poly-.epsilon.-capronamide with predicted molecular weight. Extraction of low molecular weight compounds from the crude polyamide granulate with hot water results in partial leaching of copper-based stabilizers, resulting in loss of stabilizer and reduced anti-aging effect of the polyamide products.

In order to overcome the above drawbacks, the heat-stabilizing polyamides described in French Patent No. 2,300,782, which are multi-component systems comprising

(a) an alkali metal or alkaline earth metal halide, in particular potassium iodide;

b) an organic or inorganic copper salt, in particular magnesium or copper iodide, cj divalent branched chain alcohol having 3 to 20 carbon atoms of the general formula C _n H _2n + 2O2i ^wherein the hydroxyl groups are each bonded in the position α-γ on the carbon atoms of the a hydrocarbon chain, in particular 2,2-dimethylpropylene-1,3-glycol or 2-ethylhexamethylene-1,3-glycol.

Anti-aging systems of this type are obtained, for example, by melting 2,2-dimethylpropylene-1,3-glycol with copper (I) stearate at a temperature of 150 ° C, followed by the addition of potassium iodide over 15 minutes with stirring. The product obtained is a compound which solidifies on cooling and is optionally ground into flakes or powder.

The disadvantage of using the latter anti-aging systems is that converting the polyamide granulate into a powder or mixing the polyamide melt with a solid or molten stabilizer requires the use of a separate intermediate mixing device such as screw extruders, kneaders or extruders, which complicates production considerably and increases the manufacturing costs of thermally stabilized molded polyamide products and basically eliminates the possibility of using this process for the production of polyamide fibers.

The invention solves the problem of obtaining effective heat and light stabilizers of polyamides based on copper compounds, which in addition are characterized by a higher thermal and chemical stability in contact with the melt of poly-ε-capronamide in the temperature range from 270 to 305 ° C, in the form of solutions or concentrates for coating a polyamide granulate, for mixing with a melt or injecting into a polyamide melt. The novel anti-aging agent for synthetic linear polyamides, particularly products made by molding high molecular weight poly-s-capronamide, comprises a system comprising a base active agent, a neutral liquid carrier, and other active agents having a synergistic or inhibitory effect on the base active agent.

Process according to the invention for the production of a liquid, heat-stable anti-aging agent, in particular in the form of a liquid solution or concentrate, increasing the resistance of polycaponamide products to prolonged exposure to higher temperatures ranging from 180 to 220 ° C and prolonged exposure to ultraviolet radiation in the presence of atmospheric oxygen; containing a cupric salt, an alkali metal halide and / or alkaline earth metal halide and a dihydric alcohol having at least 3 carbon atoms consists in that in a first stage gain basic active agent anti-aging agent by reacting 1 mole of copper chloride dihydrate CuCl ₂ .2 H ₂ 0 with three to five times the number of moles of oxyalkylene glycol of formula I,

(i) where is

R is a hydrogen atom and / or a methyl group and an integer from 1 to 15, in particular with diethylene glycol or triethylene glycol or dipropylene glycol or polyethylene glycol having a polymerization degree of n in the range of 3 to 15 or polypropylene glycol having a polymerization degree of n in the range of 3 to 15; heating the reactants for 0.5 to 5 hours, preferably 2 hours, at a temperature of from 80 to 150 ° C, preferably 120 ° C, with vigorous stirring while removing volatile by-products from the reaction mixture, while reacting to the reaction surface the mixture preferably introduces a stream of oxygen-free nitrogen and / or is bubbled through the reaction medium until a liquid product having a viscosity of 0.7 to 0.95 Pa.s, preferably 0.8 to 0.9 Pa.s, is obtained. , measured at a temperature of 20 ° C, without isolating the resulting active ingredient, ie copper oxyalkylene glycolate, from the excess of unreacted oxyalkylene glycol in general and, in a second step, the solution of the basic active ingredient is cooled to a temperature in the range of from 80 to 85 ° C and elemental iodine and / or an alkali metal iodide, preferably potassium iodide, is added in an amount equivalent to 3 to 5. iodine grammatomes, preferably 4 grammatomes, optionally added magnesium chloride and / or another metal chloride of the second group of the periodic group of elements to the solution of the basic active compound in the oxyalkylene glycol of the formula I obtained in the first reaction step and heated to preferably 120 ° C in an amount of 0.05 to 0.5 mole, preferably 0.15 mole, and the reaction mixture is heated at 120 ° C for up to 1 hour, then cooled to a temperature between 95 and 100 degrees Celsius, potassium iodide is added. or elemental iodine or alkali metal iodide in an amount equivalent to 0.8 to 1.1 grams of iodine, after which the reaction is allowed to proceed with stirring at 110 ° C. Celsius for 2 hours and the resulting perfectly homogeneous product is cooled to room temperature.

The anti-aging agent produced by the method of the invention provides a number of unexpected advantages in practice. In particular, in the process according to the invention, all the laborious steps necessary for the synthesis of known solid anti-aging agents based on complex copper compounds are saved; nor does it require the use of expensive chemical raw materials and complex equipment. Because of its liquid form, the anti-aging agent produced by the process of the invention is readily applied by spraying onto the surface of the polyamide granulate to form a thin layer, for example in the final stage of drying the granulate, for example in a rotary dryer, and molded products are extruded in a known manner.

The anti-aging agent produced by the method of the invention can also be introduced directly into the polyamide melt by injection into the extruder chamber, which greatly simplifies its use technology.

Shaped polyamide products, in particular high molecular weight poly-s-capronamide, stabilized by the addition of an anti-aging agent produced by the process of the invention, in an amount of 0.05 to 0.5% by weight, are virtually colorless and exhibit high resistance to prolonged exposure oxidizing agents and mechanical stress at a temperature in the range of 180 to 200 ° C, as well as ultraviolet radiation.

The invention is illustrated by the following examples, but is not limited thereto.

Example 1

17.340 g of triethylene glycol are introduced into a 30 L glass reactor equipped with a feed orifice, a mechanically driven propeller stirrer, a reflux condenser, a thermometer and a nitrogen inlet connected to a gas scrubber via a condenser. The glycol is then heated to a temperature of 80 ° C with stirring and continuously feeding an oxygen-free nitrogen stream to the surface of the liquid. Then were added 6500 g of copper chloride dihydrate CuCl _second

. 2 H ₂ O and with continuous stirring, both reactants are heated to 120 ° C. The escaping gaseous products and nitrogen are discharged from the reactor through a gas scrubber, filled with 0.1 N aqueous sodium hydroxide solution for hydrogen chloride absorption.

As already mentioned, the reactants are heated to 120 ° C with stirring and applying a stream of nitrogen to the surface of the reaction mixture. The reaction mixture is maintained at this temperature for 2 hours until the liquid homogeneous product has a viscosity of 0.8 Pa.s at 20 ° C, after which the reactor contents are cooled to ambient temperature.

The reaction product obtained is in the form of a clear liquid colored dark green and is characterized by the following parameters:

Density at 20 ° C 1,330 g / cm ³

Viscosity at 20 ° C 0.8 Pa.s

Copper ion content 10.5% by weight based on the total amount of product.

Example 2

11.560 g of triethylene glycol are charged to the reactor described in Example 1 and heated to 80 DEG C. while a constant stream of oxygen-free nitrogen is supplied to the surface of the liquid. Was added 3,250 g of copper chloride dihydrate CuCl _second 2 H ₂ O and with continuous stirring, the reactants are heated to 120 ° C. The escaping gases are removed and absorbed in a scrubber containing 0.1 N aqueous sodium hydroxide solution. The reaction is allowed to proceed at 120 ° C for 2 hours, while a stream of nitrogen is still supplied to the surface of the reaction mixture, and the reaction mixture is stirred continuously as soon as a homogeneous liquid product having a viscosity of 0.8 Pa.s at 20 ° C is formed. 12.00 g of crystalline potassium iodide are added. The reactants were then stirred at 110 ° C until the potassium iodide was completely dissolved, after which the reactor contents were cooled to 20 ° C.

The reaction product obtained is a green-brown liquid having a density of 1.71 g / cm ³ and a viscosity of 0.9 Pa.s measured at 20 degrees Celsius. Contains 4.6 wt. copper ion and 35 wt. of iodide ion, based on the total product.

Example 3

11.560 g of triethylene glycol are charged to a glass reactor as described in Example 1 and heated to 80 ° C while stirring continuously and an oxygen-free nitrogen stream is supplied to the surface of the liquid. Was added 3,250 g of copper chloride dihydrate CuCl ₂ .2 H ₂ O and the reaction mixture was under stirring heated to 120 ° C.

The escaping gases are removed from the reactor and absorbed in a scrubber containing 0.1 N aqueous sodium hydroxide solution. The reaction was allowed to proceed for 2 hours at 120 degrees Celsius while stirring continuously with a stream of nitrogen flowing to its surface. Once a homogeneous liquid product having a viscosity of 0.8 Pa.s at 20 DEG C., into a reactor, 1,305 g of magnesium chloride MgCl monohydrate _second . H ₂ O. The reaction was allowed to proceed at 120 ^C 'C for 1 hour, the reaction mixture is continuously stirred, and the surface of the liquid nitrogen stream is fed to the magnesium chloride completely dissolves. The contents of the reactor were cooled to 95 ° C and 3.195 g of potassium iodide were added. The reaction mixture is then stirred at 110 ° C until the potassium iodide is completely dissolved; the contents of the reactor are then cooled to 20 ° C.

The product is a brown liquid having a density of 1.550 g / cm @ ³ at 20 DEG C., a viscosity of 0.87 Pa.s at 20 DEG C., and a copper ion content of 6.7-7.

6.8% by weight, a magnesium ion content of 0.41% by weight, and an iodine ion content of 13.5 to 13.6% by weight.

Claims (1)

A process for the production of a liquid, heat-stable anti-aging composition, in particular in the form of a liquid solution or concentrate, increasing the resistance of molded polycaponamide products to prolonged exposure to elevated temperatures in the range 180 to 220 ° C and to exposure to ultraviolet radiation in the presence of atmospheric oxygen , an alkali metal halide and / or alkaline earth metal halide and a dihydric alcohol containing at least 3 carbon atoms, characterized in that 1 mole of copper chloride dihydrate CuCl ₂ .2 H ₂ O is reacted with three to five times the number of moles of oxyalkylene glycols of the formula I , HO - Ct (I) where is R is a hydrogen atom and / or a methyl group and an integer from 1 to 15, in particular die213339 thylene glycol or triethylene glycol or dipropylene glycol or polyethylene glycol having a polymerization degree of n in the range of 3 to 15 or polypropylene glycol having a polymerization degree of n in the range of 3 to 15; carried out in a first step by heating the reactants for 0.5 to 5 hours, preferably 2 hours, at a temperature of from 80 to 150 ° C, preferably 120 ° C, with vigorous stirring while removing volatile by-products from the reaction mixture, preferably a stream of oxygen-free nitrogen is introduced onto the reaction mixture surface and / or the stream is bubbled through the reaction medium until a liquid product having a viscosity of 0.7 to 0.95 Pa.s, preferably 0.8 to 0, is obtained, 9 Pa.s without isolating the resulting active ingredient, ie copper oxyalkylene glycolate, from the excess unreacted oxyalkylene glycol of the general formula In the second step, the solution of the basic active ingredient is cooled to a temperature in the range of from 80 to 85 ° C and elemental iodine and / or an alkali metal iodide, preferably potassium iodide, is added in an amount equivalent to 3 to 5 gramatomas. iodine, preferably 4 grammomas, optionally added to the solution of the basic active ingredient in the oxyalkylene glycol of the formula I obtained in the first reaction step and heated to a temperature of preferably 120 ° C is added magnesium chloride and / or other metal chloride in the second group an amount of 0.05 to 0.5 mole, preferably 0.15 mole, and the reaction mixture is heated at 120 ° C for up to 1 hour, then cooled to a temperature between 95 and 100 ° C, potassium iodide is added or elemental iodine or an alkali metal iodide in an amount equivalent to 0.8 to 1.2 grams of iodine, preferably 1 gram of iodine, after which the reaction is allowed to proceed with stirring at a temperature of at 110 ° C for 2 hours, and the resulting perfectly homogeneous product is cooled to room temperature.