SU591153A3 - Method of preparing linear aliphatic copolyesteramides - Google Patents

Description

: 54) METHOD FOR OBTAINING LINEAR ALIPHATIC COMPLEX SOPOLYTHRAMIDES

The duration of the reaction is determined by the fact that the resulting polyesteramide has a proportion of unreacted product and a product with low molecular weight below 15% and preferably below 10%. Reaction time 2-20 hours

The amount of unreacted product and product with a low molecular weight is estimated by the amount of benzene extraction (48 hours) in a Kumagawa instrument on ground polycondensate.

If the reaction time is too short, the proportion of unreacted product and product with a low molecular weight above 15%. The copolyester amide obtained in this way does not have good mechanical properties. .

If the reaction time is too long, the resulting products have a low melting point and modulus of rigidity.

The duration of the reaction also depends on the length of the polyester or polyamide sequences used in the reaction (the higher the molecular weight, the lower the reaction rate).

The polyamide used must have carboxyl or ester end groups. According to a known method, these polyamides are obtained by reacting, for example, polyamides with a, α-dicarboxylic aliphatic acid (succinic, adipic, sebacic). These dibasic acids can simultaneously play the role of chain stopper.

The starting polyamides are type 6-6, 6-10, 11, 12 nylons, which can be obtained by polymerization of amino acids or lactams capable of forming a linear aliphatic polyamide (for example, 11-aminoundecanoic acid, caprolactam, lyrolactam). They can also be obtained by polycondensation of diamine salts with dibasic acids (hexamethyleneamine adipate, hexamethyldiamine sebacate).

The polyesters used are obtained by polycondensation of a linear aliphatic dibasic acid. Or its diester with a, o) -linear aliphatic diol. These polyesters may have end hydroxyl groups.

As a, -diols, polyesters formed, you can use ethylene glycol, 1,3-propandiol, 1,4-butanediol, 1,6-heck sandiol, 1,10-decandiol.

As aliphatic dibasic acids suitable for the synthesis of polyesters, succinic adpinic, azelaic, sebacic, dodecanedicarboxylic acid can be used.

Used catalysts are esterification or inter-esterification catalysts (zinc acetate, lead oxide, antimony, alkyl titanates). Alkyl orthotitanates (tetraisopropyl orthotitanate, tetrabutyl orthotitanate) are preferably used.

Example 1. In a 500 ml reactor, equipped with a stirring system, gas injection and vacuum injection, 136 g of polyamide are introduced, containing end carboxyl groups with

a molecular weight of 3,600. and 90 g of polyethylene glycol polyadipate with terminal hydroxyl groups and an average molecular weight of 2400.

 This mixture is heated under nitrogen to melt, then 0.2 ml of tetraisopropyl orthotitanate is introduced with stirring and the mixture is heated to. With stirring and in a vacuum of 1 mm Hg. Art. within 4 hours The resulting product has an intrinsic viscosity of 1.0. Its melting point, which is estimated by differential thermal analysis, is 160 ° C. 20 grams of polymer is finely ground to obtain a powder with a particle size of less than 0.1 mm. Extraction from this powder is carried out with benzene for 48 hours in an extractor Kumagawa; 1.2 g of soluble polymer is thus obtained (6% of the crude polymer used). This extracted fraction consists of unreacted polyadipate.

ethylene glycol and low molecular weight polymers.

5 g of the same crude polymer is dissolved in 100 ml of concentrated sulfuric acid at room temperature. The resulting polymer solution is diluted with 1 liter of water, avoiding any heating with crushed ice. The precipitated polyamide is filtered, washed with water until neutral and dried. The dosage of the final groups determines its molecular weight, which is 2600. This analysis shows that the copolycondensate obtained by the reaction of a polyamide containing terminal carboxyl groups with polyesters contains polyamide sequences.

This sequential polyester amide is treated with an extruder, then injected under a pressure of 750 kgf / s.m into a screw press (molding temperature 220 ° C, mold temperature 20 ° C). Samples are thus obtained 2 mm thick and 50 mm long in a narrow section.

Samples that were subjected to various mechanical tests, found the following properties:

Persistence of fluidity 130 ° C; The elongation is 11% at 95kgs / cm2 at the yield threshold and 485% at 235kgs / cm2 at break;

The torsional stiffness modulus (G), depending on the temperature, varies within:

T, ° С-40 -20 О 20 40 60

G, kgf / cm2 5260 1850 1200 910 550 430 Example 2. Injected into the reactor 140 g of polyamide with terminal carboxyl groups with a molecular weight of 3000 95 g of polyadipate ethylene with a molecular weight of 2000 and 0.3 ml of tetraisopropyl orthoti 5 tanate .

Claims (2)

The reaction mixture is gradually heated with stirring under a nitrogen atmosphere to 260 ° C. make a vacuum of 1 mm Hg. Art. Polycondensation is continued under these conditions for 4 hours. The resulting product has an intrinsic viscosity of 1.5. Its melting point is 163 ° C. Samples obtained under the same conditions as in example 1 exhibit the following properties: Elongation at the threshold of yield strength is equal. 10% at 129 kgf / cm; The elongation at break is 430% at 270 kgf / cm; The torsional stiffness modulus (G) varies within: T, ° C-40-20 O 20 50 G, kgc / cm 5460 1720 1230 760 185 Example 3. A polycondensation wire, as in Example 1, is introduced gradually 77 g floor ethylene glycol with a molecular weight of 2000 150 150 g of polyamide with a molecular weight of 4000, and 0.2 ml of tetraisopropyl orthotitanate. The reaction mixture is melted, then stirred at 250 ° C for 1 hour under a nitrogen atmosphere, then this temperature is maintained in a vacuum of 1 mm Hg. Art. within 2 hours The intrinsic viscosity of the polymer obtained is 1.04, the melting point is 208 ° C, and the yield strength is 173 ° C. The elongation at the threshold of yield is 10% at 155 kgf / cm and an elongation at break of 420% at 470 kgf / cm2. The values of the modulus of rigidity in torsion (G) depending on the temperature are as follows: T, ° C-40 -20 O 20 40 60 G, KGS / CM2 8300 6500 3450 1400 650 460 Example 4. A 1 L reactor equipped with a stirring system , by the introduction of gas and vacuum, 150 g of polyadipate ethylene (with a molecular weight of 2000), its hydroxyl end groups, 300 g of a polyamide with a molecular weight of 4000, with terminal carboxyl groups, and 0.5 ml are introduced tetraisopropyl orthotitanate. The reaction mixture is brought in an inert atmosphere to a temperature of 270 ° C with stirring, this temperature is maintained for 1 hour 30 minutes, then a vacuum of 2 mm Hg is carried out. Art., and continue the reaction at the same temperature for G hour. The intrinsic viscosity of the resulting copolycondensate is -0.94, the melting point is 240 ° C, and the yield strength is 190 ° C. The elongation at the threshold of yield is 13% at 230 kgf / cm2, the elongation at break is 258% at 255 kgf / cm. The values of the torsional stiffness modulus (G) depending on temperature are as follows: T, ° C-40 -20 O 20 40 60 G, kgf / cm2 8500 6800 3500 1b50 920 900 Example 5. In hardware, identical to that used in the example , 150 g of polyamide with terminal ca. beksilnymi groups with a molecular weight of 1 / dO, 75 g of polyadipate ethylene glycol and, -4-b tandiol with a molecular weight of 2000 and i / ml of tetraisopropyl orthotitanate were added. The reaction mixture is brought to heating under a nitrogen atmosphere and with stirring, to a temperature of 260 ° C, at which the reaction is carried out for 5 hours, under a vacuum of 1 mm Hg. Art. The polycondensate obtained has an intrinsic viscosity of 0.90, a melting point of 165 ° C, and a yield strength of 110 ° C. The elongation at the threshold of fluidity is 10% at 75 kgf / cm and the elongation at break is 490% at 155 kgf / cm ... The values of the modulus of torsional rigidity (G due to temperature, are as follows: T ° C-40-20O 20 40 G, KGS / CM2 4220 1175 640 304 140 Example 6. As described in Example 1, 119 g of polyamide with terminal carboxyl groups with a molecular weight of 3,600 and 81.5 g of polyadipate 1,4-butanediol with terminal hydroxyl groups and molecular weight of 2400. The reaction mixture is heated with stirring to melt in a stream of nitrogen. When the temperature reaches 225 ° C, 0.2 ml of tetrama then bring the temperature up to 250 ° C, then create a vacuum of 1.5 mm Hg, and continue the reaction for 5 hours. The characteristic viscosity of the polymer obtained is 1.09 and the melting point is 205 ° C. The resulting linear aliphatic copolyester amides are suitable for the manufacture of non-elastomeric molded products that resist shock. Claim 1. Method for producing linear aliphatic copolyester amides by polycondensation at 230-280 ° C at a pressure of 0.1-2 mm t. Art. linear aliphatic polyamide, shedding carboxyl or ester terminal groups with a molecular weight of 1000-10000 and a linear aliphatic polyester with terminal hydroxyl groups with a molecular weight of 500-6000, in the presence of alkyl orthotitanate as a catalyst, characterized in that products suitable for the manufacture of semi-rigid, non-elastomeric molded products, resistant to impact and having a yield strength of 105-200 ° C, an elongation at the yield strength below 20% and a modulus of rigidity at teaching defined by Meod Klasha and Berg, 300-3000 kgf / cm at 20 ° C, the starting polyamide and polyester are used in weight ratios of 1.5: 1 - 20: 1. 2. The method according to claim 1, characterized in that, in order to obtain copolyester amides having a yield strength of 105-200 ° C, an extension at the yield threshold is less than 15% and a modulus of torsional stiffness of 300-1500 kgf / cm with t5911538 20 ° C, polyamide with molecular is used. Information sources accepted in the range of 2000-5000 and polyester with molecular substance during examination: weighing 2000-4000 with weight ratios x1. Patent of France No. 1485341, cl. C 08 g 1.5: 1 - 10: 1.1967.