WO2002062895A1

WO2002062895A1 - A polyamide/polyisobutylene composition and method of its preparation

Info

Publication number: WO2002062895A1
Application number: PCT/CZ2002/000007
Authority: WO
Inventors: Ludek Toman; Ivan Kelnar; Petr Vlcek; Miroslav Janata
Original assignee: Ústav Makromolekulární Chemie Akademie Ved Ceske Republiky
Priority date: 2001-02-09
Filing date: 2002-02-07
Publication date: 2002-08-15
Also published as: CZ291312B6; CZ2001528A3

Abstract

The solution concerns a polyamide/polyisobutylene composition that consists of a mixture of polyamide and/or copolyamide/polyisobutylene and compatibilizer and/or of a mixture of polyamide or copolyamide and compatibilizer whereby the compatibilizer is polyisolbutylene functionalized with isocyanate and subsequently with lactam and/or amide containing in the chain at least one structure unit with a group of general formula I and/or II located in the end group or along the chain, where Z represents H or CH3. The reactive group NHCONHCOR' and/or Y is linked to the benzene ring either directly or through a linear or branched alkyl group R with 1-10 carbon atoms, R' is an aliphatic or aromatic group, Y is a lactam grouping, where n equals 3-11. The compositions in question are prepared by mixing polymer blends at temperatures ranging between 150 and 300 °C, preferably at 240-260 °C.

Description

A Polyamide/polyisobutylene Composition and Method of its Preparation

Technical Field

The invention concerns a polyamide/polyisobutylene composition, in particular the composition containing polyisobutylene functionalized with isocyanate and subsequently with a lactam and/or amide, and the method of its preparation.

Background Art

Polyisobutylenes (PIB) are materials highly resistant to chemicals including sulphuric acid. With the development of synthesis of block copolymers or reactive polymers, polyisobutylenes had resisted functionalization for a long time. In the early 1980's only, telechelic α,ω-dihydroxypolyisobutylenes (HO-PIB-OH) were prepared by controlled cationic polymerization and consecutive multistep syntheses (B. Ivan, J. P. Kennedy, N.S.C. Chang, J. Polym. Sci., Polym. Chem. Ed. 18, 3177 (1980)). Telechelic dihydroxypolyisobutylenes became starting materials for preparation of other reactive polyisobutylenes: for example, HO-PIB-OH was converted to PIB bisurethanes by the reaction of HO-PIB-OH with excess toluene diisocyanate (ΝCO/OH -10/1). However, multistep syntheses going from α,ω-dichloropolyisobutylene (J. P. Kennedy, B. Ivan, Designed Polymers by Carbocationic Macromolecular Engineering, Theory and Practice, Hanser Publisher, New York 1991, p. 178) require thorough purification of intermediates and removing reactants and, in addition, only the functional end groups are exchanged, while the PIB backbone remains unchanged.

Only recently, according to a Czech Patent Application (PN 1998-1931, L. Toman, P. Nlcek, Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic), a method of direct synthesis of reactive multifunctionalized PIB with isocyanate groups along the chain has been discovered. A simple, but effective single- step synthesis of PIB functionalized with isocyanate groups consists in cationic copolymerization of isobutylene with 3-isopropenyl-α,α-dimethylbenzyl isocyanate affording a product, which contains the reactive groups both in the end groups and along the PIB chain. The isocyanate groups on benzene rings can be subsequently functionalized in situ with a lactam or amide, according to a Czech Patent Application

(PN 2000-1306, L. Toman, P. Nlcek, Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic). For their outstanding properties and linear macromolecules, polyamides found use as a fibre material and, for the same reason, in machinery as a construction plastic

(stressed parts such as toothed wheels, bearing bushes, car parts, etc.).

However, polyamides also have a number of drawbacks. All polyamides are hygroscopic, the sorbed water content being variable depending on the air humidity. Their water sorption depends on the concentration of polar ΝHCO groups in the polymer. These circumstances must be considered in application of polyamides because, as a consequence, mechanical properties such as tensile strength and toughness as well as the dimensions of products change. Hence, they are not applicable in cases where dimension precision is required. To improve these unfavourable properties, blends of polyamides and polyolefms are mostly prepared, which must be compatibilized using appropriate compatibilizers to achieve good mechanical properties. Examples of such blends are:

Polyethylene (PE)/PA 6 (L.A. Utracki, M. M. Dumoulin, P.Toma, Polym. Eng. Sci. 26, 34, 1986); polypropylene (PP)/PA 6 (B. Liang, J.L. White, J.E. Spraiell, B. C. Goswami, J. Appl. Polym. Sci. 28, 2011, 1983); compatibilized maleic anhydride- grafted PP/PA 6 (F. Ide, A. Hasegawa, J. Appl. Polym. Sci. 18, 963, 1974); ethylene- methacrylic acid copolymer/PA6 (W.J. Macknight, R.W. Lenz, P. N. Musto, R.J. Somani, Polym. Eng. Sci. 25, 1124, 1985); chemically modified PE/PA 6 (H. K. Chuang, CD. Han, J. Appl. Polym. Sci. 30, 165, 1985); J. Appl. Polym. Sci. 30, 2457, 1985); ethylene-vinyl acetate copolymer/PA 6 (CD. Han, H. K. Chuang, in Morphology of Polymers, B. Sedlacek, Ed., Walter de Gruyter, Berlin, 1986 p.103); L. D'Orazino, C. Mancarella, E. Martuscelli, A. Casale, A. Filippi, F. Speroni, J. Mater. Sci. 21, 989, 1986; J. Mater. Sci. 22, 429, 1987); PA6/EPR rubber compatibilized with maleic anhydride- or succinic anhydride-modified EPR ( S. Cimmino, L. D'Orazio, R. Greco, G. Maglio, M. Malinconico, C. Mancarella, E. Martuscelli, R. Palumbo, G. Ragosta, Polym. Eng. Sci. 24, 48, 1984; E. Martuscelli, F. Riva, C Sellitti, C. Silvestre, Polymer 26, 270, 1987). From literature search follows (and from monograph R.Puffr, N. Kubanek, Lactam-Based Polyamides Nolume I -II, CRC Press, Boston 1991) that polyisobutylene has not been used for polyamide modification. The reason is that no substance has been so far known which would be able to compatibilize polyamide/PIB blends.

Disclosure of Invention

The subject of the present invention is a polyamide/polyisobutylene based composition consisting of a polyamide/polyisobutylene and/or a copolyamide/polyisobutylene blend and a compatibilizer and/or of a polyamide/compatibilizer and/or copolyamide/compatibilizer whereby the compatibilizer is polyisobutylene functionalized with isocyanate groups and, subsequently, with lactam and/or amide, containing in the chain at least one structure unit of general formula I or II

(I) (II)

as an end group and/or along the chain, where Z is hydrogen or methyl. The reactive

-NHCONHCOR' and/or Y groups are linked to the benzene ring directly or through a linear or branched alkyl group R with 1-10 carbon atoms, R' is an aliphatic or aromatic group, Y is a cyclic lactam grouping

-NHCON CO

where n = 3-11. The polyamide phase in the composition according to the present invention is a high-molecular-weight compound containing in the main chain -CONH- groups, which occur in the arrangements a, b and c.

-CONH CONH CONH CONH (a)

-CONH -NHCO CONH -NHCO (b)

-CONH NHCO CONH CONH (c)

The structures can be prepared by polycondensation of diamines and dicarboxylic acids such as hexamethylenediamine and adipic acid (PA6/6), polycondensation of amino acids such as 11-aminoundecanoic acid or mixed products (c), or by polymerization of cyclic lactams with 4-12 carbon atoms such as 2- pyrrolidone, hexano-6-lactam and dodecano-12-lactam.

The polyisobutylene phase in the composition according to the invention is an isobutylene homopolymer or copolymer, with advantage polyisobutylene-cø-polyiso- prene and polyisobutylene -co-polystyrene.

Another feature of the invention is that the functionalized polyisobutylenes used as compatibilizers have molecular weights 600 - 200 000 ( „) and functionality 1-30 (F). The compatibilizer content in polyamide or copolyamide/polyisobutylene blends ranges from 1 to 20 vol. %, with advantage from 2 to 10 vol. % and its content in the blends with polyamide or copolyamide alone is 1-99 vol. %. In the composition according to the present invention, the polyisobutylene content in polyamide or copolyamide/polyisobutylene blends is 5-95 vol. %.

The further object of the present invention is the method of preparation of the composition, which consists in performing compatibilization and mixing of polymer blends in the temperature range of from 150 to 300 °C, preferably at 240 to 260 °C. The mixing and compatibilization of polymer blends according to the invention is performed in the presence of tin compounds such as dibutyltin dilaurate or dibutyltin diacetate in concentrations of 0.01-0.08 vol. %. The compatibilizers are prepared by the procedure in which first the copolymerization of IB with 3-isopropenyl-α,α-dimethylbenzyl isocyanate is performed at a temperature below -10 °C in the presence of a Lewis acid, such as tin tetrachloride. After the addition of a termination agent such as a tertiary amine, with advantage triethylamine (TEA), which neutralizes the Lewis acid, such as tin tetrachloride and makes it possible to replace a low-boiling solvent with a high-boiling one, the reaction of the isocyanate groups with linear or cyclic amides (lactams) is finally performed at a temperature above 60 °C, or the formed PIB-(NCO)_n is directly dosed to the lactam or amide melt.

The molar ratio of the tertiary amine to the total concentration of the Lewis acid in the reaction mixture is 1-10³, preferably 5 and the molar ratio amide/isocyanate groups is 1-10³, with advantage 5. The reaction with amides is performed either in high- boiling solvents or in their mixtures having a boiling point higher than 60 °C, in which both PIB-(NCO)_n and amide are soluble, with advantage in toluene or in the amide melt. Polyisobutylenes functionalized with isocyanate and subsequently with lactam or amide with molecular weights M_n ranging from 600 to 200 000 are oily, pasty, rubber-like or solid. It is well known that polyisobutylene, in the absence of a compatibilizer, deteriorates mechanical properties of polyamide blends and their mixtures, such as PA6/PIB 80/20 vol. %, and the resulting mixtures show insufficient mechanical properties in common applications (see, e.g., Table 1). However, addition of a minute amount, e.g. 3 vol. %, of the functionalized PIB according to the invention, markedly improves mechanical properties of the original blend reaching the values quite sufficient for common applications. Moreover, the notch toughness of the obtained composition containing 5 vol. % of compatibilizer is two times higher than that of neat PA6 used in the blend preparation and approaches the properties of tough Nylon of the PA6/EPR 80/20 vol. % type (Ex. 1, Table 1). Outstanding resistance to chemicals, excellent flexibility even at low temperatures down to -50 °C, extraordinary resistance to oxygen and ozone, minimum permeability to gases, hydrophobic nature, electroinsulating properties predestine the polyisobutylene elastomers, after the discovery of the compatibilization effect of the functionalized PIB according to the invention, for industrial production of materials based on PA/PIB blends. Polyisobutylene elastomers, which are also the best vibration dampers, impart their outstanding properties to the blends and the compositions prepared according to the invention, with notch toughness considerably higher than that of neat PA can be assumed to find wide utilization as construction plastics. The plastics can find application in electronics, building industry, military field, health, transportation, manufacture of sport utilities and toys. They could be exploited especially in shock- and vibration-damping materials such as handles or grips of drilling machines, circular saws, revolvers, tommy-guns, machine guns, etc.

Figures

Fig. 1 Morphology of a PA6/PIB blend prepared according to Example 1 (80/20 vol. %;

B, Table 1) with visualised PIB domains.

Fig. 2 The same blend but containing a compatibilizer (PIB-K) in a concentration of 3 vol. % (J, Table 1) and 5 vol. % (K, Table 1) with a distinctly finer phase structure.

Examples

The method of preparation of tough polyamide and a polyamide/polyisobutylene composition containing isocyanate-functionalized polyisobutylene subsequently functionalized with lactam or amide is illustrated on several examples without being restricted to them. In the given examples, copolymerizations of IB and 3-isopropenyl- , -dimethylbenzyl isocyante (IDBI) carried out in the presence of a Lewis acid, for example tin tetrachloride in a Buchi autoclave (further only reactor) of a total volume of 250 ml or 500 ml. For copolymerization and dosing of the components there was used the same technique and drying of chemicals as described in the Czech Patent No. 280752, i.e., under dry conditions generally used in cationic polymerizations. Also in the absence of humidity and under inert atmosphere, with advantage under argon, were performed the consecutive reactions of isocyanate groups in the PIB chain: either in the same copolymerization reactor provided with a reflux condenser, or the reaction mixture was transferred with overpressure of an inert into a dry three-neck 500-ml glass flask provided with a heating mantle, magnetic stirrer, reflux condenser, three-way stopcock and thermometer, or the formed PIB-(NCO)_n was dosed under an inert into the same flask as in the preceding case, but containing the lactam or amide melt. Molecular weights ( _n) of the products were determined by GPC in tetrahydrofuran (THF), the structure of products was analyzed by NMR and IR spectroscopy. The functionality (E) was calculated from Η NMR spectra of products. The first step of the synthesis, i.e. the preparation of PIB-(NCO)_n ( _n, F) was checked by transformation of NCO groups in samples to urethanes by the reaction with methanol using dibutyltin dilaurate as catalyst according to Czech Patent Application PN 1998-1931. PA/PIB, PA/PIB/compatibilizer and PA/compatibilizer blends were usually prepared by 10 min mixing at 250 °C in a laboratory discontinuous Brabender kneader at 50 rpm/min with the W50EH kneading chamber. Mechanical testing of samples was performed in the dry state, immediately after workup. Pieces for Instron 6025 strength tests were prepared after cooling and disintegration by injection molding at 260 °C Type L pieces with a very sharp notch were used for impact tensile toughness tests according to DIN 53448.

The following polymers were used for the preparation of blends: (a) Polyisobutylenes (Oppanols, BASF) B50 (M_n = 120 000), B80 (M_n = 200 000), B 100

(M„ = 250 000);

(b) Nylon 6 (PA6, Ultramid B3, BASF) (M„ =18 000) [NH(CH₂)₅CO]_n (dried at 70 °C for 24 h in vacuum before use);

(c) Nylon6/6 (PA6/6, Zytel 101, E.I. duPont Co.) (M_n =17 000) [NH(CH₂)₆NHCO(CH₂)₄CO]_n (dried at 70 °C for 24 h in vacuum before use);

(d) Isobutylene - isoprene copolymer (IB-IP copolymer) (M_n =180 000, unsaturation 2 mole %) prepared according to Czech Patent 220 233.

Example 1 The synthesis of polyisobutylene functionalized consecutively with isocyanate and lactam is visualized by the general scheme: (1) Cationic copolymerization of IB/RNCO mixture (RNCO = IDBI)

m CH₂=C(CH₃)₂ + n RNCO > \R ΛR V\ΛΛ/\ΛR/V\ = PIB(NCO)_n

NCO NCO NCO

(2) Reaction of NCO groups with lactam (Ln) (x = 3-11).

PIB(NCO)_n + n NH CO > PIB(NHCO-N CO)_n

L(CH₂) L(CH₂)J

PIB-(NCO.Ln)_n To a mixture of IB (0.53 mol), IDBI comonomer (0.04 mol) and dichloromethane (40 ml) was added tin tetrachloride (0.015 mol) in the temperature range from -50 to -70 °C.

The copolymerization gave a yield of 30 g of PIB-(NCO)₅ with functionality ranging from 4 to 6. The reaction was stopped by addition of TEA (0.14 mol) and 80 ml of toluene while stirring. Then the isocyanate groups were reacted with hexano-6-lactam

(Ln6). Ln6 (0.133 mol) was dosed into the reactor in a toluene solution (150 ml) and the mixture was refluxed for 10 h. The product was isolated by precipitation of the toluene solution into excess of methanol and dried in vacuo at 40 °C for 5 days. The product,

PIB-(NCO.Ln6)_n, with functionality F-5 and molecular weight ca. 8000 (M_n) was used as compatibilizer (PIB-K) for preparation of composition PA6/PIB/PIB-K. The blends of the following compositions (DBSnDL is dibutyltin dilaurate) were mixed for 10 min:

A- PA6 (100 vol. %) [50 g].

B- PA6/PIB, B50 (-80/20 vol. % ) [40 g PA6, 9 g PIB]. C- PA6/PIB, B80 (-80/20 vol. %) [40 g PA6, 9 g PIB]. D- PA6/PIB, B50 (-60/40 vol. %) [30 g PA6, 15.5 g PIB]. E- PA6/PIB, B100 (-40/60 vol. %) [20 g PA6, 27.5 g PIB].

F- PA6/PIB, B50 (-80/20 %vol.), PIB-K (-1.5 vol. %) [40 g PA6, 8.5 g PIB and 0.75 g PIB-K)]. G- PA6/PIB, B50 (-80/20 vol. %), PIB-K (-3 vol. %) [40 g PA6, 7.5 g PIB a 1.5 g PIB- K)]. H- PA6/PIB, B80 (-80/20 vol. %), PIB-K (-3 vol. %) [40 g PA6, 7.5 g PIB a 1.5 g PIB-

K)]. I- PA6/PIB, B50 (-80/20 vol. %), PIB-K (-5 vol. %) [40 g PA6, 6.5 g PIB a 2.5 g PIB- K)].

J- PA6/PIB, B50 (-80/20 vol. %), PIB-K (-3 vol. %) and DBSnDL (~ 0.06 vol. %)

[40 g PA6, 7.5 g PIB, 1.5 g PIB-K) and 0.03 g DBSnDL]. K- PA6/PIB, B50 (-80/20 vol. %), PIB-K (-5 vol. %) and DBSnDL (~ 0.04 vol. %) [40 g PA6, 6.5 g PIB, 2.5 g PIB-K) and 0.02 g DBSnDL]. L- PA6/PIB, B50 (-60/40 vol. %), PIB-K (-3 vol. %) and DBSnDL (~ 0.08 vol. %) [30 g PA6, 16.5 g PIB, 1.5 g PIB-K) and 0.04 g DBSnDL]. M- PA6/PIB, B80 (-40/60 vol. %), PIB-K (-3 vol. %) a DBSnDL (~ 0.08 vol. %) [20 g

PA6, 26 g PIB, 1.5 g PIB-K) and 0.04 g DBSnDL]. N- PA6/EPR (80/20 vol. %) [50 g].

Mechanical properties of PA6 and of PA6/PIB, PA6/PIB/PIB-K and PA6/EPR (80/20 vol. %) are given in Table 1.

TABLE 1

Sn is DBSnDL, σ - stress at break, ε - strain at break, E - Young modulus, a_t - toughness (impact tensile strength); measurements were performed at laboratory temperature (~ 22 °C). The results in Table 1 show an increase in strain of almost one order due to compatibilizer PIB-K when comparing the same blends B and J. It can be also observed that the toughness of the material (F, G, I) increases with increasing content of PIB-K in the composition almost two times (K) compared with the original PA6 (A).

Example 2

To a mixture of IB (0.53 mol), IDBI comonomer (0.05 mol) and dichloromethane (40 ml) was added tin tetrachloride (0.015 mol) in the temperature range from -55 to -75

°C. The copolymerization was performed up to the yield -30 g of PIB-(NCO)₉ with functionality ranging from 8 to 10. The reaction was stopped by addition of TEA (0.14 mol) and 80 ml of toluene while stirring. Then the isocyanate groups were reacted with 0.133 mol of hexano-6-lactam (Ln6) or 2-pyrrolidone. The products formed, PIB(NCO.Ln6)₉ and PIB(NCO.Ln4)₉, of molecular weights -18 000 (M_n) were purified and dried by the procedure according to Example 1 and then used as compatibilizers (PIB-K) for preparation of compositions PA6/PIB (-80/20 vol. %)/PIB-K. The compositions containing 40 g PA6, 7.5 g PIB, B50 and 1.5 g PIB-K had the following mechanical properties: σ - 46 MPa, ε - 120 %, E - 1210 MPa, a_t - 60 kJ.m^"2.

Example 3 The synthesis of isocyanate-functionalized PIB was carried out by the procedure according to Example 1. The product was dosed into the lactam Lnl2 melt and subsequently isolated by precipitation into methanol. After purification and drying, PIB(NCO.Lnl2)₅ of molecular weight 10 000 (M_n) was used as compatibilizer for composition PA6/PIB (-80/20 vol. %)/PIB-K. The composition containing 40 g PA6, 7.5 g PIB, B50, 1.5 g PIB-K, and 0.03 g DBSnDL showed the following mechanical properties: σ ~ 48 MPa, ε ~ 115 %, E ~ 1150 MPa, a_t - 55 kJ.m^"2.

Example 4

Compatibilizer PIB-K was synthesized according to Example 3 and used for preparation of PA6/copolymer IB-IP (-80/20 %)/PIB-K blend. The composition containing 40 g PA6, 6.5 g IB-IP copolymer, and 2.5 g PIB-K showed the following mechanical properties: σ ~ 50 MPa, ε ~ 85 %, E ~ 1250 MPa, a_t ~ 61 kJ.m^"2. Example 5

0.02 mol of tin tetrachloride was added to a stirred mixture of isobutylene (1.03 mol), IDBI comonomer (0.06 mol) and dichloromethane (90 ml) at - 65 °C The copolymerization was conducted up to the yield - 60 g, when the PIB-(NCO)₅ precursor of functionality F -5 was formed. The copolymerization was stopped by addition of TEA (0.4 mol) and the reaction mixture was diluted with 200 ml of toluene. Then it was divided under argon into two flasks, which contained 150 ml of previously prepared warm (- 50 °C) toluene solution of a) benzamide (BzA 0.18 mol)) or b) acetamide (Ac A 0.18 mol). The consecutive reactions of isocyanate groups with the amides were performed similarly to lactams according to Example 1, i.e., first by distilling off volatiles and then refluxing the reaction mixture for 18 h. The products were purified and dried according to Example 1. PIB-(NCO.BzA)₅ and PIB-(NCO.AcA)₅ (M_n = 8000 ± 300, F = 5.3 ± 0.3) were used as compatibilizers (PIB-K) for preparation of compositions PA6/6/PIB(~80/20 vol. %)/PIB-K. The blends containing 40 g PA6/6, 7.5 g PIB,B50, 1.5 g PIB-K, and 0.02 g DBSnDL showed the following mechanical properties: σ - 46 MPa, ε -95 %, E ~ 1210 MPa, a_t = 53 kJ.m^"2 (PIB-K with aliphatic amide) and 58 kJ.m^" (PIB-K with aromatic amide). Mechanical properties of the neat

PA6/6 were as follows: σ ~ 72 MPa, ε -190 %, E -1475 MPa, a_ -35 kJ.m^' -2

Example 6

Compatibilizers PIB-K of molecular weights (M_n) and functionalities (F), respectively, (a) 8 000 and F -5, (b) 18 000 and F -9 prepared according to Examples 1 and 2 were used for preparation of compositions PA6/PIB-K. The blends of composition (a) 48.5 g PA6 and 1.5 g PIB-K and (b) 47.5 g PA6 and 2.5 g PIB-K showed the following mechanical properties: (a) σ ~ 72.4 MPa, ε -150 %, E -1680 MPa, α_t~ 23.4 kJ.m^"2; (b) σ -71.2 MPa, ε -160 %, E ~ 1540 MPa, α_t~ 30.4 kJ.m^'2.

Claims

1. The composition based on polyamide/polyisobutylene, characterized in that it J consists of a mixture of polyamide and/or copolyamide/polyisobutylene and compatibilizer and/or of a mixture of polyamide and/or copolyamide and compatibilizer, wherein the compatibilizer is the polyisobutylene functionalized with isocyanate and subsequently with a lactam or amide containing in the chain at least one structure unit with a group of general formula I or II

HCONHCOR'

(I) (II)

at the end of or along the chain, where Z represents H or CH₃ and the reactive group - NHCONHCOR' or group Y is bonded to the benzene ring either directly or tlirough a linear or branched alkyl group R with 1-10 carbon atoms, R' is an aliphatic or aromatic group, Y is a lactam group, where n equals 3-11

-NHCON CO

2. The composition according to Claim 1, characterized in that the polyamide phase in the polyamide or copolyamide/polyisobutylene blend is a high-molecular-weight compound containing in the backbone -CONH- groups, which may occur in arrangement a, b or c

-CONH CONH CONH CONH (a)

-CONH -NHCO CONH -NHCO (b)

-CONH NHCO CONH CONH (c) which can be prepared by polycondensation of diamines and dicarboxylic acids such as hexamethylenediamine and adipic acid (PA6/6), polycondensation of amino acids such as 11 -amino undecanoic acid or mixed products, or by polycondensation of lactams with carbon number 4-12, such as butano-4-lactam, hexano-6-lactam and dodecano-12-lactam.

3. The composition according to Claim 1, characterized in that the polyisobutylene phase in the polyamide and/or copolyamide/mixture is a homopolymer or copolymer of isobutylene, with advantage poly(isobutylene-co-isoprene) or poly(isobutylene- co-styrene).

4. The composition according to Claims 1-3, characterized in that the functionalized polyisobutylenes have molecular weights 600-200 000 (M_n) and functionality (F)l- 30.

5. The composition according to Claims 1-4, characterized in that the compatibilizer content in the polyamide and/or copolyamide/polyisobutylene mixture is 1-20 vol. %, with advantage 2-10 vol. % and its content in the blend with neat polyamide or copolyamide is 1-99 vol. %.

6. The composition according to Claims 1-5, characterized in that the polyisobutylene content in the polyamide or copolyamide/polyisobutylene is 5-95 vol. %.

7. The method of preparation of compositions according to Claims 1-6, characterized in that compatibilization and mixing of polymer blends is performed at temperatures ranging between 150-300 °C, with advantage at 240-260 °C.

8. The method of preparation according to Claim 7, characterized in that mixing and compatibilization of polymer mixtures is performed in the presence of tin compounds such as dibutyltin dilaurate and/or dibutyltin diacetate in concentrations 0.01-0.08 vol. %.