FR2490656A2 - Thermoplastic elastomeric co:polyether:ester:amide(s) - by condensing carboxy terminated aliphatic polyamide(s) with hydroxy terminated aliphatic polyoxyalkylene(s) - Google Patents

Abstract

High mol. wt. thermoplastic elastomers with aliphatic polyetheresteramide blocks having alternating sequences of linear aliphatic polyamide blocks with a mol. wt. of 500-3000 and polyoxyalkylene blocks with a mol. wt. of 500-5000, linked by ester functions, are made with the following properties: wt. ratio of polyether to polyamide sequences, 45/55 to 85/15; m.pt. 140-220 deg.C; Vicat softening point 60-150 deg.C; elastic elongation 30-200%; elongation at break 700-1000%; torsional modulus 100-300 kg/cm2 at 20 deg.C; and compression deformation 10-30% at 20 deg.C. Prods. are thermoplastic materials which can be processed by injection mouldings, calendering, extrusion, etc., to form articles having good elastomeric properties without the necessity for vulcanisation.

Description

 The main French patent No. 2,401,947 relates to a process for the synthesis of copolyetheresteramides which consists in polycondensing under vacuum of 0.10 to 2 mm of Hg between 200 and 3000 of the aliphatic polyamide sequences at the end of COOH chains with polyoxyalkylene sequences for of hydroxylated chains in the presence of a specific catalyst of this sequencing reaction which is a zirconium or hafnium tetralkoxide of general formula M (OR) 4 in which the alkyl radical comprises a number of carbon atoms between 1 and 24 .

 According to the process described in patent n02,401,947 the proportion of polyether blocks can vary between 5 and 85%.

 To obtain rigid non-elastomeric products, the preferred proportion of polyether used is from 10 to 50% by weight.

 The illustrative examples of the main patent all relate to rigid products.

 According to the present application, it has been found that if the proportion of polyether introduced at the start was between 45 and 85%, preferably between 60 and 80%, it was possible, under the same operating conditions as those described in French patent n02,401,947, to obtain Colorless or lightly colored elastomeric copolyetheresteramides having physical and mechanical characteristics comparable to those of natural or synthetic rubbers and which make it possible to be able to use them in applications such as seals, transmission bellows for motor vehicles, film fibers elastomeric, membranes, play balls.

 Compared to rubbery substances, these products have certain advantages, in particular an implementation that does not require vulcanization, a colorless appearance, sometimes even transparent, which makes artificial coloring easier. On the other hand, it is possible to easily recover waste by recycling.

 These products have a density close to 1, flexibility which is maintained even when cold and good impact resistance at low temperature.

 The operating conditions are the same as those described in French patent n02,401,947.

 The polyamides involved are nylons 6, 6-6, 6-10, 6-9, 11 or 12 which have been treated with an aliphatic diacid to give them ends of carboxylic chains.

 The molecular weights of the polycarboxylic polyamide sequences involved are between 500 and 3000.

 Polyethers are polyoxyalkylereglycOzsobtenés by polymerization of oxides of ethylene, propylene or tetrahydrofuran.

 Their molecular weight is between 500 and 5000.

The reaction is carried out around 2600C under a vacuum of 0.5 to 2 Torr in the presence of 0.1 to 5% of a zirconium or hafnium tetralkoxide or a mixture of dexes as catalyst
It is possible to use compounds Zr (OR) 4 or
H f (OR) 4 whose chain is between 1 and 24 carbon atoms. However, it is preferred to use the tetrabutyl or tetraisopropyl alkoxy derivatives.

The control and identification measures chosen to characterize the separate products are as follows
- VICAT OC point (expressed according to ASTM D 1525 65T) v
- intrinsic viscosity (determined at 250C in solution in
metacresol) at 0.5 g per 100 ml.

- tensile elongation (measured according to ASTM D standard
638 67 T).

- torsion module (measured according to ASTM D 1043 61 T
according to the method of CLASH and BERG).

The HAZEN coloration is determined in a 5% by weight solution of polymer in freshly distilled metacresol with a "CMPARATOR 1000 LOVIBOND device equipped with a standard DB 416 lighting device, a device
Nessler DB 412 and 113 mm Nessler A.306 tubes.

 The following examples are given without implied limitation to illustrate the invention.

EXAMPLE 1
13.0 kg of polycaprolactam are introduced into a 90 l reactor for the purpose of carboxylic chains of average molecular weight equal to 1300, which has been obtained according to a conventional process by polymerizing caprolactam in the presence of adipic acid, and adding 13.0 kg of polyoxyethylene glycol of molecular weight equal to 1300 and 95 g of tetrabutylorthozirconate Zr (OBu) 4.

After having purged the air from the reactor with a stream of nitrogen, the mixture is brought under operation to a vacuum of 1 Torr and heated to 2600C temperature which is maintained for 2 hours 25 minutes.

 After cooling the reaction mixture, a mistletoe product is obtained with an intrinsic viscosity equal to 1.40. The product is elastic.

- the VICAT point under 1 kg is equal to 1250C,
- the melting point is equal to 1950C
- Shore D hardness is equal to 44
- the elongation is 30% under 50 kg / cm2 at the lock point
750% under 360 Kg / cm2 at break.

 - the torsional stiffness module according to the CLASH and BERG method is 700 kg / cm2 at -400C and 225wNg / cmo 20 20 C.

EXAMPLE 2
According to a procedure analogous to that described in Example 1, 6.0 kg of dicarboxylic polyamide 6 of average molecular weight equal to 500 is introduced successively into the reactor, 24.0 kg of polyoxytetramethylene glycol of average molecular weight equal to 2000, 10 g of zirconium tetrabutoxide. Reacted under vacuum of 1 Torr at 2600C for 5 hours. After cooling, one collects a white tomera which has an intrinsic viscosity of 1.65, a VICAT point of 980C and a melting point of 1750C.

Shore D hardness is 61.

The elongation is 180% at 20 Kg / cm2 at the flow threshold and 980% at 320 Kg / cm2 at break.

Hazen coloring = 10.

EXAMPLE 3
In a 2 1 reactor, 200 g of polylaurolactam are introduced for the purpose of adipic chains of average molecular weight equal to 850 which was obtained according to a conventional process by polymerizing laurolactam in the presence of adipic acid, 470 g of polyoxytetramethylene glycol of molecular weight are added. equal to 2000 and 2.25 g of tetrabutylorthozirconate Zr (OBu) 4
After having purged the air from the reactor with a stream of nitrogen, the mixture is brought under operation to a vacuum of 1 Torr and heated to 2600C temperature which is maintained for 2 hours After cooling of the reaction mixture, one obtains a white product with an intrinsic viscosity equal to 1.97. The product is elastic.

- the VICAT point under 1 Kg is equal to 810C
- the elongation is 106% at 27 Kg / cm2 at the threshold
flow rate and 900% at 305 Kg / cm2 at break
- Hazen coloring = 10.

EXAMPLE 4
According to a procedure analogous to that described in Example 3, carried out in the presence of 2.77 g of hafnium tetrabutoxide. Reacted in vacuo at 2600C for 2 hours. After cooling, a white elastic product is collected which has an intrinsic viscosity of 1.95 and a point
VICAT of 800C.

The elongation is 106% at 27 Kg / cm2 at the flow threshold and 920% at 300 Kg / cm2 at break.

Hazen coloring = 15.

Claims (8)

1 - Process for the preparation of polyether-ester-amides  colorless sequenced elastomers by reaction to state  melted from a dicarboxylic polyamide, the functions of which  COOH are located at the ends of the chain, with a  hydroxylated polyoxyalkylene glycol at the ends of the  chain, in the presence of one or more tetraalkoxides  as a catalyst, characterized in that the  or said tetraalkoxides used as catalyst  have the general formula M (OR) 4 in which M  represents zirconium or hafnium and the R, identical  or different, denote linear alkyl radicals  or branched having from 1 to 24 carbon atoms, the propor  polyether by weight introduced at the outset being  between 45 and 85 eÓ. 2 - Method according to claim 1, characterized in that  the symbols R, identical or different, of the formula  defining zirconium or hafnium tetraalkoxides  are C1 to C8 alkyl radicals. 3 - Process according to claim 1 or 2, characterized in that  that the catalyst is formed by the association of one or  several of the tetraalkoxides with one or more alcohol  tes of formula (R1O) pY in which Y - denotes a metal  alkaline or alkaline earth, p is the valence of Y and R1  represents a monovalent hydrocarbon residue, in part  culier an alkyl radical in C1 to C24 and preferably  in C1 to C8. 4 - Method according to one of claims 1 to 3, character  in that the proportion of catalyst varies from 0.01  at 5%, by weight of the mixture of the dicarboxylic polyamide and  polyoxyalkylene glycol. 5 - Method according to one of claims 1 to 4, character  laughed in that the average molecular weight of the polyamide  dicarboxylic is between 500 and 3000. 6 - Method according to one of claims 1 to 5, character  laughed in that the average molecular weight of the polyoxyal  coylene glycol is between 500 and 5000. 7 - Method according to one of claims 1 to 6, characterized  in that the weight proportion of polyoxyalkylene glycol  based on the total weight of dicarboxylic polyamide and  polyoxyalkylene glycol reacted is between 45 and  85% and preferably between 50 and 80% /; 8- Method according to one of claims 1 to 7, characterized  in that the temperature chosen for the implementation of  the melt reaction, which is greater than the points  of polyamide dicarboxylic and polyoxyalkylene  glycol, is preferably around 2600C. 9- Method according to one of claims 1 to 8, characterized  in that the melt reaction is carried out under  a more or less high vacuum, in particular under a vacuum  on the order of 0.05 to 5 mm of mercury.  10-Polyether-ester-amides obtained by the following process-one  of claims 1 to 9.  11- Applications of the products according to claim 10 such as  elastomers.