KR100600460B1 - Thermoplastic polymer composition based on polyamide - Google Patents

Abstract

The present invention relates to polyamide based thermoplastic polymer compositions which exhibit a good balance of properties, in particular mechanical properties. The compositions exhibit high stiffness, high ductility or impact strength, and satisfactory action, especially at relatively high temperatures.

The composition of the present invention comprises, in addition to polyamide, a copolymer comprising a rubber grafted with acrylonitrile and a styrene compound, and lamellar inorganic particles.

Description

Polyamide Based Thermoplastic Polymer Composition {THERMOPLASTIC POLYMER COMPOSITION BASED ON POLYAMIDE}

The present invention relates to polyamide based thermoplastic polymer compositions exhibiting good compromises in properties, in particular in mechanical properties. The compositions exhibit high stiffness, high ductility or impact strength, and satisfactory action, especially at relatively high temperatures.

The properties that often need to be controlled for thermoplastics to be formed by techniques such as injection molding, gas injection molding, extrusion or extrusion-blow molding are particularly high in stiffness, impact strength, dimensional stability and low shrinkage after molding. , Ability to be painted by various processes, surface appearance and density. These properties can be controlled within certain ranges by the selection of polymers or by the addition of compounds of different properties to the polymers. In the latter case, the condition is "polymer composition". The choice of material for a given application typically depends on the level of performance required for that particular property and its cost. There has been a steady study of new materials that can meet the above mentioned in terms of performance and / or cost. For example, polyamides are widely used materials, especially in the automotive industry.

Polyamides are polymers that have chemical resistance, are stable at high temperatures, and can be kneaded with other kinds of polymers to modify their properties. For example, it is possible to add elastomeric polymers to improve toughness.

Polymer blends comprising polyamides and polyphenylene oxides (PPO) are known. These polymer blends exhibit good mechanical properties, for example, suitable for the production of automotive body parts. However, they are expensive and result in interest in other polymer blends including polyamides. Moreover, they exhibit high shrinkage and very unsatisfactory surface appearance after molding. Thus, there have been studies of compositions that can exhibit the same level of mechanical properties, in particular in terms of stiffness and impact strength, without exhibiting these drawbacks.

Polymer blends are known which comprise polyamides and acrylonitrile-butadiene-styrene (ABS). In these blends, these two incompatible polymers are usually compatible with the maleic anhydride functional groups possessed by ABS or other polymers. Such compatible polyamide and ABS based compositions exhibit properties associated with individual compounds. Document EP 648 811 describes a polymer blend comprising, for example, a compatibilizer consisting of polyamide, ABS, a styrene-maleimide polymer grafted with maleic anhydride, and an ethylene-propylene elastomer grafted with maleic anhydride. . The kneaded material exhibits excellent impact strength and high chemical resistance at low temperatures due to the polyamide.

The surface appearance and paintability of polyamide and ABS base compositions are particularly appreciated. However, the modulus of elasticity, and the heat distortion temperature of these compositions are not satisfactory for various applications. Post-molding shrinkage for these parts is very high, to some extent.

In order to modify the properties of polyamides, it is known to use plate-like nanoparticles derived from, for example, montmorillonite. For example, it is known that the heat deformation temperature and rigidity can be improved by introducing montmorillonite into the polyamide. The presence of montmorillonite does not provide any improvement in impact strength. Typically, this tends to lower the impact strength rather. For example, document WO 00/09571 describes a process for the preparation of a composition comprising nanoparticles derived from polyamide and montmorillonite, which do not reduce the impact strength of the polyamide. This is still insufficient.

Document WO 00/31185 describes a composition comprising polyamides, elastomers and nanoparticles. These compositions exhibit insufficient properties. When nanoparticles are used in an amount sufficient to substantially improve the stiffness of the composition, soft-brittle transitions appear with insufficient impact resistance at the operating temperature. Compositions comprising only polyamides, elastomers and nanoparticles exhibit satisfactory stiffness and insufficient impact strength, or exhibit satisfactory impact strength and insufficient stiffness. The relative decrease in impact strength caused by the presence of nanoparticles in compositions comprising nanoparticles and elastomers is very large. Moreover, these compositions exhibit surface appearance and paintability that are not entirely satisfactory for a particular application.

It is an object of the present invention to provide novel polymer compositions based on polyamides and ABS which exhibit improved compromises in properties, in particular impact strength, stiffness, heat distortion temperature, molding shrinkage, surface appearance and paintability.

To this end, the present invention provides a thermoplastic composition comprising the following compounds:

Compound A: thermoplastic polyamide,

Compound B: a styrene compound selected from styrene and α-methylstyrene and a copolymer grafted with acrylonitrile and, where appropriate, a copolymer comprising a functional group for compatibility with polyamide,

Compound C: one or more agents for compatibility between the polyamide and the compound B, where appropriate, one or more of which include functional groups for compatibility with the polyamide,

Compound D: where appropriate, an elastomeric compound,

Compound E: lamellar inorganic particles exhibiting a molding factor of greater than 5 and a small dimension of less than 10 nm.

The composition according to the invention can be obtained according to various methods, some of which methods will be described in more detail below. During these methods, compounds A, B and E, optionally compounds C and D, and more optionally another compound, are used during a single operation or during multiple operations. These methods form thermoplastic compositions that can be molded by conventional methods.

It is mentioned that the composition can include other compounds. These may in particular be stabilizing, strengthening, coloring, flame retardant or catalyzed compounds. The composition may also include inorganic fillers such as kaolin, wollastonite or talc, or reinforcing fibers such as glass fibers or carbon fibers. These other compounds or fillers or fibers may be introduced into the composition during the latter stage of preparation, or during the preparation of each of Compounds A and / or B and / or C and / or D and / or E. Compositions according to the invention that do not comprise inorganic fillers or reinforcing fibers exhibit a particularly advantageous compromise between density and mechanical properties: the materials exhibit high impact strength and high rigidity for densities that are kept low.

The composition according to the invention preferably exhibits a polyamide (compound A) continuous phase in which the nodules comprising compound B are dispersed. For this purpose, the compound advantageously comprises more polyamide than compound B. Polyamide and Compound B are immiscible. Dispersion of compound B in polyamides is facilitated by the presence of functional groups for compatibility with polyamides. These functional groups may be retained by Compound B, or a compatibilizer commonly compatible with Compound B. Compatibility makes it possible to improve the action of the composition.

Compound E exhibits a molding factor of greater than 5 and consists of lamellar inorganic particles with small dimensions of less than 10 nm. The term “shaping factor” is understood to mean the ratio between the large dimension index of the shape of the particle and the small dimension index of the shape of the particle. In the case of lamellar particles, the small dimension is the thickness. These particles are dispersed in the composition. The quality of the dispersion can vary: this allows the composition to exhibit aggregates of lamellar particles. The particles are preferably dispersed in polyamide. However, it is possible for the particles to be present in other compounds, such as compound B.

The dispersed particles constituting Compound E are usually obtained from a compound exhibiting a structure in the form of a sheet. During the preparation of the composition, the sheets separate from each other to form particles. The small dimensions of the particles are substantially of the sheet. The geometry of the particles, ie their shape and dimensions, can be observed in the composition by microscopy or can be similar to the shape and dimensions of the sheets of compounds from which they are obtained. As mentioned above, it is possible to ensure that the sheets do not completely separate and that aggregates are present in the composition.

Next, various compounds of the composition will be described in detail.

Compound A

Compound A is a thermoplastic polyamide. It may be a single polyamide or a mixture of various polyamides. In the latter case, the kneaded material may be obtained by operation prior to the preparation of the composition, or may be obtained during the preparation of the composition using different or simultaneously polyamides.

The polyamide may be selected from:

Polyamides of the type obtained from lactams and / or amino acids,

Polyamides of the type obtained from diacids and diamines,

Copolyamides of these two polyamides.

Polyamide 6, polyamide 11, polyamide 12, polyamide 4,6, polyamide 6,6, polyamide 6,10, polyamide 6,36, copolyamide 6 / 6,6 and 6 / 6,36 Very particular preference is given to polyamides selected from kneadings and copolymers based on these polyamides and copolyamides.

Compound A is advantageously based on polyamide 6,6. It may be polyamide 6,6 alone or a mixture of polyamide 6,6 and polyamide 6. In the kneaded material, the weight ratio of polyamide 6 to the total weight of polyamide is preferably 1 to 30%.

Polyamide 6,6 based compositions exhibit good mechanical properties, good heat resistance properties and high hardness. They are particularly suitable for electrophoretic coating methods in which high temperatures are applied to the material.

The presence of polyamide 6,6 in combination with polyamide 6 may enable improvement of certain mechanical properties, in particular by reducing post-molding shrinkage and improving compatibility between polyamide and compound B.

According to a preferred feature, the polyamides 6,6 used alone or as kneaders advantageously comprise more amine end groups than acid end groups. This feature improves the surface appearance, mechanical properties and / or compatibility of the product formed from the composition. The amount of amine end groups is preferably more than 50 meq / kg, and the difference in the amount of amine end groups and acid end groups is preferably more than 5 meq / kg, even more preferably more than 10 meq / kg. The amount of amine and / or acid end groups is determined by potentiometric titration after dissolution of the polyamide. The method is described, for example, in "Encyclopedia of Industrial Chemical Analysis", volume 17, page 293, 1973.

Compound B

Compound B is a copolymer comprising a styrene compound selected from styrene and α-methylstyrene and a rubber grafted with acrylonitrile. The copolymer is thermoplastic. It may additionally contain functional groups intended to improve compatibility with polyamides. The copolymer preferably comprises 10 to 90% by weight of rubber. The content of rubber in the entire compound B is preferably 15 to 35% by weight.

The rubber is preferably polybutadiene, butadiene-styrene rubber, butadiene-acrylate rubber, butadiene-acrylonitrile rubber, EPR (ethylene-propylene rubber) and EPDM (ethylene-propylene-diene rubber), and these two or more rubbers Is selected from the group consisting of kneaded mixtures.

Compound B can be prepared by conventional methods such as grafting styrene compound monomers and acrylonitrile monomers to rubber. This can be done by bulk, solution or suspension polymerization. It is also possible to combine these two or more kinds of polymerization methods, for example, bulk solution polymerization, bulk suspension polymerization or emulsion suspension polymerization. The polymerization is preferably carried out in the presence of standard substances such as free radical donors, optionally in combination with redox systems, chain regulators, stabilizers, suspending agents, emulsifiers and the like.

Compound B is advantageously an acrylonitrile-butadiene-styrene copolymer. The weight content of butadiene in the compound is, for example, 15 to 35%, and the weight content of styrene relative to the weight of styrene and acrylonitrile is preferably 20 to 80%, preferably more than 50%. Compound B can be, for example, an acrylonitrile-butadiene-styrene copolymer having a proportion of acrylonitrile, butadiene and styrene of approximately 25%, 25% and 50%, respectively.

In certain embodiments, Compound B comprises functional groups for compatibility with polyamides. These groups are advantageously selected from maleic anhydride, carboxylic acid and ester groups. Such groups are obtained, for example, by using comonomers such as maleic anhydride or acrylamide during the preparation of compound B.

Compound C

The composition may comprise one or more agents for compatibility between the polyamide and compound B. At least one of these agents includes functional groups for compatibility with polyamides. In the presence of various agents, the kneaded material can be obtained by operation prior to the preparation of the composition, or can be obtained during the preparation of the composition using the same or successive various compatibilizers.

The functional groups for compatibility present in one or more agents may have the same properties as those optionally present in compound B. They are advantageously selected from maleic anhydride, carboxylic acid and ester groups. The group is derived from a comonomer such as maleic anhydride used during the preparation of compound C.

According to an embodiment where compound B comprises a group for compatibility with polyamides, the composition advantageously does not comprise compound C.

As compatibilizers, mention is made of styrene-maleimide copolymers grafted with functional groups selected from anhydrides and carboxylic acids. The term "styrene-maleimide copolymer" is understood to mean a polymer which represents a unit calculated from the styrene and maleimide units of formula (I):

[Formula I]

Wherein R is selected from hydrogen, alkyl radicals or aromatic or arylaromatic radicals.

R is, for example, a phenyl group. The maleimide unit can be selected from, for example, N-phenylmaleimide, N- (o-methylphenyl) maleimide, N- (m-methylphenyl) maleimide or N- (p-methylphenyl) maleimide. The copolymer can be obtained, for example, by copolymerizing styrene with maleic anhydride and then partially reacting with an amine such as aniline to form maleimide units from the anhydride units. Anhydride units that do not react with the amine constitute the functionalization. Another method consists in directly copolymerizing styrene, maleimide and maleic anhydride.

As a compatibilizer, a styrene-maleimide copolymer grafted with maleic anhydride in which the weight ratio of the various units is 40 to 60% styrene units, 40 to 60% N-phenylmaleimide units and 0.1 to 5% maleic anhydride units. Very particularly preferred. These copolymers have particularly good mechanical and thermal properties that make the composition particularly effective for properties evaluated at relatively high temperatures.

The composition may also comprise an ungrafted styrene-maleimide copolymer.

As compatibilizers, mention is also made of styrene-ethylene-butadiene-styrene or styrene-butadiene-styrene block copolymers which, when appropriate, represent functional groups for compatibility with polyamides, in whole or in part, hydrogenated, such as maleic anhydride functional groups. . Such compounds are known to those skilled in the art. Copolymers of this type are commercially available, for example, in the Kraton range from Shell. More particularly, mention is made of styrene-ethylene-butylene-styrene copolymers modified with maleic anhydride (SEBS-g-MA). The weight ratio of the agent in the composition is advantageously from 0.5 to 10%. Preferably less than 5%.

As the compatibilizer, both styrene-maleimide grafted with maleic anhydride and SEBS grafted with maleic anhydride can be used advantageously.

As the compatibilizer, styrene-acrylonitrile copolymers grafted with maleic anhydride, or even maleic anhydride directly introduced during the preparation of the composition, may also be used.

Compound d

The composition may comprise an elastomeric compound. Such compounds are typically used to modify the toughness of the composition. The weight ratio of compound D in the composition is preferably at most 50% by weight, even more preferably at most 10% by weight. According to a preferred feature of the invention, the compound is grafted with a functional group selected from acid anhydrides and carboxylic acids. Grafting of copolymers with acid anhydrides is usually obtained by copolymerization in the presence of maleic anhydride.

Elastomers that can be used as toughness modifiers are defined as having an ASTM D-638 tensile modulus of less than about 40000, typically less than 25000, preferably less than 20000. These may be random, block or graft copolymers or homopolymers. Useful rubbery polymers can be prepared from reactive monomers that can form the chain or branched portion of the polymer or can be grafted to the polymer. These reactive monomers can be dienes or carboxylic acids and derivatives thereof such as esters and anhydrides. Among these rubbery polymers, butadiene polymer, butadiene / styrene copolymer, polyisoprene, polychloroprene, acrylonitrile / butadiene copolymer, polyisobutylene, isobutylene / butadiene copolymer, ethylene / propylene copolymer (EPR) Or ethylene / propylene / diene copolymers (EPDM) will be mentioned. Useful rubbery polymers may include polymers obtained from vinylaromatic monomers, olefins, acrylic acid or methacrylic acid, and derivatives thereof and metal salts thereof, respectively. Useful rubbery polymers are described in patents US-A-4 315 086 and US-A-4 174 358.

The first preferred toughness modifier for the practice of the present invention is a functionalized copolymer which is a copolymer of ethylene with α-olefins other than ethylene, with functional groups such as carboxyl or anhydride grafted to the ethylene copolymer. Ethylene and α-olefins are preferably copolymers of ethylene and an α-olefin selected from at least C ₃ -C ₈ α-olefins, preferably C ₃ -C ₆ α-olefins. Propylene is preferred as the C ₃ -C ₈ α-olefin monomer of the copolymer. Instead of or in addition to propylene of the copolymer, other C ₃ -C ₆ α-olefins such as 1-butene, 1-pentene and 1-hexene may be used. For carrying out the invention according to a preferred form, mention may be made of (functionalized) ethylene-propylene rubber grafted with maleic anhydride and ethylene-propylene-diene rubber grafted with maleic anhydride.

Compound E

As mentioned above, the dispersed particles constituting Compound E are usually obtained from a compound exhibiting a structure in the form of a sheet. During the preparation of the composition, the sheets separate from each other to form particles. Separation of sheets is often known as peeling, splitting and cracking. The processes involved during the separation may vary depending on the compound used and / or the process used. They produce particles with high or low shaping coefficients, small dimensions of less than 10 nm. Smaller dimensions, such as the thickness of the particles, are even more preferably less than 2 nm.

Compounds having a lamellar structure can be selected from various classes. Fluoromica, zirconium phosphate, silicates, more specifically phyllosilicates, or hydrotalcites are mentioned.

Lamellar silicates suitable for the practice of the present invention include montmorillonite, smectite, illite, sepiolite, palygorskite, muscobite, allervardite, amecite, hectorite, talc, fluorohectorite, saponite, Baydelite, nontronite, stebencite, bentonite, mica, fluoromica, vermiculite, fluoro vermiculite or halosite are mentioned. These compounds may be of natural, synthetic or modified natural origin. Montmorillonite is very particularly preferred.

Separation (cracking, splitting, etc.) of the sheet into lamellas can be facilitated by pretreatment with organic compounds, such as organic compounds capable of increasing the distance between sheets. Treatment properties may depend on the properties of the compound having a structure in the form of a sheet. For example, for the treatment of montmorillonite, mention is made of treatment with ionium compounds, ie substituted ammonium or phosphonium compounds. Pretreated montmorillonite is commercially available. Methods of incorporating compounds having various treatments and / or sheet-like structures into thermoplastic resins, such as polyamides, are disclosed.

As for the treatment of montmorillonite, and optionally other compounds having structures in the form of sheets, mention is made, in particular, of treatment by the exchange of cations initially present in the compound. These are, for example, organic cations of the ionium type. The organic cation may be selected from phosphonium and ammonium, such as primarily quaternary ammonium. For example, mention may be made of protonated amino acids such as 12-aminododecanoic acid protonated in ammonium, mainly tertiary amines and protonated in quaternary ammonium. The chain bonded to the nitrogen or phosphorus atom of onium may be aliphatic, aromatic or arylaliphatic and linear or branched, and may represent oxygen containing units such as hydroxyl or ethoxy units. As examples of the organic ammonium treatment, dodecyl ammonium, octadecyl ammonium, bis (2-hydroxyethyl) octadecylmethylammonium, dimethyldioctadecylammonium, octadecylbenzyldimethylammonium or tetramethylammonium may be mentioned. As examples of organic phosphonium treatments, alkylphosphoniums such as tetrabutylphosphonium, trioctyloctadecylphosphonium or octadecyltriphenylphosphonium can be mentioned. These lists are not of a limiting nature.

Silicates in the form of sheets suitable for the practice of the present invention include montmorillonite, smectite, illite, sepiolite, palygorskite, muscobite, allervardite, amesite, hectorite, talc, fluorohectorite, saponite, It may be selected from beadelite, nontronite, stebencite, bentonite, mica, fluoro mica, vermiculite, fluoro vermiculite or halosite. These compounds may be of natural, synthetic or modified natural origin.

로 시판되는 유기 화합물로 처리한 클레이가 사용될 수 있다. 또한, Nanocor 사에서 Nanomer range 로 시판되는 몬모릴로나이트 기재의 클레이가 사용될 수 있다.According to a preferred embodiment of the present invention, the composition consists of polyamide resin and lamellar particles obtained by stripping of phyllosilicates, such as montmorillonite, pre-swelled by ion exchange, dispersed in the resin. Examples of swelling treatments that can be used are described, for example, in patent EP 0 398 551. Any known treatment to promote peeling of the phyllosilicate in the polymer matrix can be used. For example, the trade name Cloisite from Laporte

Clays treated with commercially available organic compounds can be used. In addition, montmorillonite based clays commercially available from Nanocor in the Nanomer range can be used.

Any method that enables the obtaining of dispersion of particles in a polymer can be used to carry out the invention. The first method is preferred by kneading a compound having a structure in the form of a sheet to be dispersed, optionally for example with a swelling agent, in the molten polymer and then optionally placing the kneaded material under high shear, for example in a twin screw extrusion apparatus. Consists of obtaining a dispersion. The polymer is understood as one of the compounds given individually, preferably as polyamide, or as a mixture of various compounds of the composition. Another method consists of kneading a compound to be dispersed, optionally for example with a swelling agent, with a monomer in a polymerization medium and then polymerizing. In this case, the polymer is preferably polyamide. For example, a lamellar compound, optionally a treated lamellar compound, is introduced into a medium comprising a polyamide monomer and then polymerized to give a polyamide (compound A) comprising compound E. Another method consists in kneading the polymer and the concentrated kneading of the prepared dispersed particles with the molten polymer, for example according to one of the methods described above.

The weight ratios of the various compounds are preferably as follows:

Compound A: 5 to 95%, preferably 30 to 70%

Compound B: 4.9 to 94.9%, preferably 20 to 40%

Compound C: 0-30%, preferably 5-20%

Compound D: 0 to 30%, preferably 1 to 10%

Compound E: 0.1-30%, preferably 1-10%.

Next, the method that can be used for the preparation of the composition according to the present invention will be described in detail.

Thermoplastic compositions are typically obtained by kneading the various compounds involved in the composition, the thermoplastic compounds being in molten form. Depending on the nature of the various compounds, high or low temperatures and high or low shear forces are used. The compounds can be introduced simultaneously or sequentially. Typically, an extrusion apparatus is used that heats the material, exerts a shearing force, and transports it. Such devices are well known to those skilled in the art.

According to the first embodiment, all the compounds are melt kneaded in a single operation such as an extrusion operation. For example, a granulated polymer material is kneaded, introduced into an extrusion apparatus, melted, and subjected to high or low shear, Compound E, or more typically a treated compound having a lamellar structure to form particles during the preparation of the composition. It is possible to introduce. In this method, it is preferred to work under relatively high shear to promote cleavage of the lamellae.

In certain embodiments, it is possible to prepare premixes of some compounds prior to preparation of the final composition.

According to a particular embodiment, the process for the preparation of the composition according to the invention comprises the following operations:

a) preparation of a composite material comprising compound A and compound E,

b) melt kneading the composite material and compound B.

The composite material prepared in step a) can be obtained by one of the following processes:

The polymerization of the polyamide in the presence of any treated compound having a structure in the form of a sheet or compound E in the form of particles. In this process, the polyamide prepared above is preferably based on polyamide 6 and the monomers are mainly selected from caprolactam and / or 6-aminocaproic acid.

Melt kneading of polyamide with compound E in the form of particles or any treated compound having a structure in the form of a sheet. The kneading can be carried out using an extrusion apparatus, preferably at high shear.

The composite material obtained in step a) constitutes the premix. This will be melt kneaded with other compounds during operation b), for example using an extrusion apparatus as described above. During the operation b), polyamides containing no compound E can be added. Then, from the polyamide of the composite material and the polyamide added during operation b), the polyamide constituting the compound A included in the composition is produced.

The composition according to the invention, when produced using an extrusion apparatus, is preferably conditioned in the form of granules.

This, or typically, more specifically granules are those formed using a method comprising melting to produce a product. Thus, the product consists of the composition.

The use of the composition according to the invention is particularly advantageous in the manufacture of products for the automotive industry, in particular for the manufacture of body parts.

Other details or advantages of the invention will become more apparent in light of the examples given below by way of illustration only.

Compound used

Compound A1: polyamide 6,6 with a relative viscosity of 2.90 comprising 55 meq / kg of amine end group and 40 meq / kg of acid end group, sold as Technyl 29 AP NH by Rhodia Engineering Plastics.

Compound A2: a polyamide with a relative viscosity of 3.0 as marketed as Toplamid 1021 by the company Hyosung Corporation 6.

Compound B1: Acrylonitrile-butadiene-styrene copolymer sold as Terluran EHI-5 by BASF Korea.

Compound B2: acrylonitrile-butadiene-styrene copolymer sold by Kumho as Kumho 795.

Compound C1: styrene-maleimide grafted with maleic anhydride, comprising 46% by weight of styrene, 53% by weight of N-phenylmaleimide and 1% by weight of maleic anhydride, sold as PSX 0371 by the company Nippon Shokubai (N- Phenylmaleimide) copolymers.

Compound C2: hydrogenated styrene-ethylene-butylene-styrene (SEBS) grafted with maleic anhydride, sold as FG1901X by the company Shell.

Compound D1: ethylene-propylene elastomer, grafted with maleic anhydride, sold as MP 0620 by the company Mitsui Chemical.

Compound E1: montmorillonite treated with methyldihydrooctadecylammonium.

Compound E2: Southern Clay Corp. Montmorillonite treated with quaternary ammonium salt, marketed by SCPX 2086.

Composite 1: Polyamide 6 matrix comprising 3.9% by weight (ash) of dispersed montmorillonite nanoparticles obtained by polymerization from a medium comprising montmorillonite and caprolactam treated with ammonium dodecanoic acid.

Compound F1: lubricant, carbon black, nigrosine.

Preparation of the composition

The composition was prepared by melt kneading using a twin screw extruder of the Werner-Pfleiderer ZSK type. Extrusion conditions were as follows:

Temperature: 240-280 ° C.,

Rotational speed: 200 to 300 revolutions / minute,

Throughput: 25 to 30 kg / hr.

Two different processes were used:

Process 1: kneading each compound in an extruder,

Process 2: Kneading the composite comprising polyamide and lamellar particles in an extruder.

evaluation

Several tests were performed on the composition:

Yield point stress according to ASTM D638 standard, measured after conditioning test specimens at 23 ° C. and 50% relative humidity.

Measuring after conditioning the test specimens at elongation at break, 23 ° C. and 50% relative humidity in accordance with ASTM D638 standard.

Measured after conditioning test specimens at flexural modulus, 23 ° C. and 50% relative humidity in accordance with ASTM D790 standard.

-Measuring after conditioning the test specimen at flexural stress, 23 ° C. and 50% relative humidity according to ASTM D790 standard.

Notched Izod impact strength according to ASTM D236 standard, measured at 23 ° C., in dry condition, under impacts of 3.2 t and 6.4 t.

Heat distortion temperature (HDT) according to ASTM D648 standard, measured under loads of 4.6 kgf / cm 2 and 18.5 kgf / cm 2.

Mold shrinkage: ratio of (molding machine length-size of molding test specimen) / (length of molding machine) to ASTM test specimens of 200 mm length and 3.2 mm thickness (the length is measured in the injection direction of the test specimen).

Rockwell hardness according to ASTM D785 standard.

Density according to ASTM D792 standard.

Yield point stress according to ISO 527, measured at 23 ° C and 50% relative humidity, after conditioning the test sample.

Measuring after conditioning the test specimens at elongation at break, 23 ° C. and 50% relative humidity according to ISO 527 standards.

Measured after conditioning the test specimen at flexural modulus, 23 ° C. and 50% relative humidity in accordance with ISO 178 standards.

Measuring after conditioning the test specimen at flexural stress according to ISO 178 standard, 23 ° C. and 50% relative humidity.

Notched Izod impact strength according to ISO 180 / 1A standard, measured at 23 ° C., in dry condition, under impacts of 3.2 t and 6.4 t.

Notched Charpy impact strength according to ISO 179 / 1eA standard, measured at 23 ° C. in dry state, under impacts of 3.2 t and 6.4 t.

Vicat A / 120 hardness according to ISO 306 standard.

-Vortex Test (melt fluidity):

After forming the composition into granules and melting, in an Engel 80T press, a spiral having a rectangular cross section of thickness 2 mm and width 2.4 mm, at an injection pressure of 100 bar and an injection rate of 60 mm / s, at a barrel temperature of 240 to 260 ° C. Injection into the molding machine. Injection time is 5 seconds. The result is indicated by the length of the molding machine with the composition filled exactly. The composition evaluated in this test has a pre-molding moisture content of 0.1%.

Examples 1-4

Various compositions corresponding to various examples (1, 2, 3, 4) and comparative examples (C1, C2, C3, C4, C5) and evaluation thereof are shown in Tables I and II below.

Example C1 C2 One 2 3 4 Compound a1 67% 54% 56% 53% 49% 47% Compound a2 10% 10% 10% 10% 10% Compound B1 15% 20% 20% 20% 20% 20% Compound c1 10% 10% 10% 10% 10% 10% Compound E1 3% 3% 5% 5% Compound d1 7% 5% 3% 5% 7% Compound F1 One % One % One % One % One % One % Property exam unit Tensile stress at yield point ASTM D638 kgf / ㎠ 606 622 705 630 614 596 Elongation at break ASTM D638 % 40 42 33 39 43 40 Flexural modulus ASTM D790 kgf / ㎠ 23610 23490 29720 27540 28540 27470 Flexural stress ASTM D790 kgf / ㎠ 921 910 1075 976 945 900 Notched Izod impact at 3.2 t ASTM D256 kgf.cm/cm 25.3 44.2 15.5 22.6 20.4 21.5 Notched Izod impact at 6.4 t ASTM D256 kgf.cm/cm 23.7 25.7 13.2 21.0 18.1 19.1 HDT at 4.55 kgf / ㎠ ASTM D648 ℃ 182.0 167.8 166.3 174.3 177.3 171.6 HDT at 18.5 kgf / ㎠ ASTM D648 ℃ 90.3 84.0 95.9 93.3 100.0 107.2 Molding shrinkage REP Korea % 1.57 1.41 1.16 1.24 0.95 0.95 Rockwell Hardness ASTM D785 R-scale 116.0 116.2 118.3 116.6 114.8 113.5 density ASTM D792 g / cm 3 1.099 1.099 1.121 1.111 1.105 1.100 Tensile stress at yield point ISO 527 KJ / ㎡ 57.7 61.0 68.7 61.5 60.1 57.5 Elongation at break ISO 527 % 46 67 35 50 40 36 Flexural modulus ISO 178 KJ / ㎡ 2351 2258 2818 2585 2735 2648 Flexural stress ISO 178 KJ / ㎡ 86.3 91.3 102.9 94.3 92.1 88.4 Notched Izod Shock ISO 180 / 1A N / mm2 9.7 8.8 6.7 9.7 11.6 15.1 Notched Charpy Shock ISO 179 / 1eA N / mm2 12.2 15.9 7.7 12.0 18.5 17.5 Vicat A / 120 Hardness ISO 306 251.3 245.8

Example 4 C3 C4 5 C5 Compound a1 Compound a2 100% 70% Compound B1 20% 20% 20% Compound c2 2 % Compound c1 10% 10% 10% Compound E1 Compound d1 5% Complex 1 70% 100% 63% Compound F1 Property exam unit Tensile stress at yield point ASTM D638 kgf / ㎠ 801 1003 760 654 721 Elongation at break ASTM D638 % 22 2.6 150 47 53 Flexural modulus ASTM D790 kgf / ㎠ 36450 43350 25500 29360 25440 Flexural stress ASTM D790 kgf / ㎠ 1264 1576 1000 998 1058 Notched Izod impact at 3.2 t ASTM D256 kgf.cm/cm 12.3 5.5 5.5 53.5 13.8 Notched Izod impact at 6.4 t ASTM D256 kgf.cm/cm 13.6 4.0 4.5 27.2 10.9 HDT at 4.55 kgf / ㎠ ASTM D648 ℃ 172.5 196.3 170 151.7 141.6 HDT at 18.5 kgf / ㎠ ASTM D648 ℃ 101.8 145.6 65 107.6 75.8 Molding shrinkage REP Korea % 0.78 1.02 1.28 0.82 0.76 Rockwell Hardness ASTM D785 R-scale 120 119.5 120 116.7 119.5 density ASTM D792 g / cm 3 1.124 1.144 1.14 1.102 1.106 Tensile stress at yield point ISO 527 KJ / ㎡ 79.5 102.1 78 64.7 69.5 Elongation at break ISO 527 % 18 2.6 100 42 48 Flexural modulus ISO 178 KJ / ㎡ 3550 4251 2600 2875 2448 Flexural stress ISO 178 KJ / ㎡ 1256 150.2 105 98.2 98.6 Notched Izod Shock ISO 180 / 1A N / mm2 7.8 4.8 4.7 42.7 7.2 Notched Charpy Shock ISO 179 / 1eA N / mm2 9.5 6.7 5.5 45.5 8.5 Vicat A / 120 Hardness ISO 306 ℃ 204.8 213.3 214 203.5 205.2

Example 5

The prepared compositions are shown in Table III below.

Example 5 C6 (Comparative Example) Compound a2 53% 53% Compound B2 30% 32% Compound c1 10% 10% Compound d1 5% 5% Compound E2 2 % -

Evaluation of these compositions is shown in Table VI below.

Example Property exam unit 5 C6 density ASTM D792 g / cm 3 1.0831 1.0835 Tensile stress at yield point ASTM D638 kgf / ㎠ 550.5 531.2 Flexural modulus ASTM D790 kgf / ㎠ 24330 21450 Flexural stress ASTM D790 kgf / ㎠ 859.7 812.3 Notched Izod impact at 3.2 t ASTM D256 kgf.cm/cm 84.67 77.2 Notched Izod impact at 6.4 t ASTM D256 kgf.cm/cm 37.7 26.84 Rockwell Hardness ASTM D785 R-scale 113.9 115.1 HDT at 4.55 kgf / ㎠ ASTM D648 ℃ 131.7 128.2 HDT at 18.5 kgf / ㎠ ASTM D648 ℃ 109.1 103.6 Helix length Cm 325 235

Compositions comprising montmorillonite exhibit higher melt fluidity than compositions not containing montmorillonite and exhibit similar mechanical properties.

Claims (31)

A thermoplastic composition comprising the following compound: Compound A: 5-95% by weight of thermoplastic polyamide, Compound B: a copolymer comprising 4.9 to 94.9% by weight of a styrene compound selected from styrene and α-methylstyrene and rubber acrylonitrile grafted, Compound E: Lamellar inorganic particles having a molding factor of greater than 5, less than 10 nm, from 0.1 to 30% by weight. The composition according to claim 1, wherein the polyamide constitutes a matrix in which the nodule of Compound B is dispersed. The composition of claim 1 or 2, wherein the lamellar particles are dispersed in a polyamide. The composition according to claim 1 or 2, wherein compound B is a copolymer based on acrylonitrile-butadiene-styrene. delete The composition according to claim 1 or 2, wherein the functional group for compatibility with the polyamide is selected from maleic anhydride, carboxylic acid or ester groups. The composition according to claim 1 or 2, wherein the polyamide is selected from polyamide 6, polyamide 6,6, and kneaded materials and copolymers based on these polyamides. 8. A composition according to claim 7, wherein compound A is a mixture of polyamide 6,6 and polyamide 6 comprising 1 to 30% polyamide 6 relative to the total weight of polyamide. 8. The composition of claim 7, wherein the polyamide 6,6 contains more amine end groups than acid end groups. 10. The composition of claim 9, wherein the amount of amine end groups is greater than 50 meq / kg, and the difference between the amounts of amine end groups and acid end groups is greater than 5 meq / kg. The composition according to claim 1 or 2, wherein the lamellar inorganic particles are obtained from a compound exhibiting a structure in the form of a sheet selected from silicates, fluoromicas, zirconium phosphates or hydrotalcites. 12. The composition of claim 11, wherein the lamellar particles are obtained from montmorillonite, or a compound derived from montmorillonite. 13. The composition of claim 12, wherein the lamellar particles are obtained from montmorillonite treated with an agent that separates the sheet. delete The composition of claim 1 or 2, wherein the weight ratios of the various compounds are as follows: Compound A: 30-70% Compound B: 20-40% Compound E: 1-10%. delete A method for producing a composition according to claim 1 or 2, characterized by melt kneading the compound. A process for preparing a composition according to claim 1, characterized in that it comprises the following operations: a) preparation of a composite material comprising compound A and compound E, b) melt kneading the composite material and compound B. 19. The method of claim 18 wherein the composite material is prepared by one of the following processes: Polymerization of polyamides in the presence of compounds having a structure in the form of sheets capable of producing lamellar particles or compounds E in the form of particles, Melt kneading of a compound having a structure in the form of a sheet capable of producing lamellar particles or a compound E in the form of particles with polyamide. delete The composition according to claim 1 or 2, which is used for the production of automotive body parts. The composition of claim 1, wherein compound B is a copolymer comprising a functional group for compatibility with polyamide. A thermoplastic composition comprising the following compound: Compound A: at least 5% by weight and less than 95% by weight thermoplastic polyamide, Compound B: a copolymer comprising a styrene compound selected from styrene and α-methylstyrene and at least 4.94% by weight and less than 94.9% by weight of grafted rubber with acrylonitrile, Compound C: an agent that is greater than 0% and no greater than 30% by weight of at least one agent for compatibility between polyamide and compound B, wherein at least one of them comprises a functional group for compatibility with polyamide, Compound D: greater than 0 wt% and no greater than 30 wt% of the elastomeric compound, Compound E: Lamellar inorganic particles having a molding coefficient of more than 5 and less than 10 nm of 0.1 wt% or more and 30 wt% or less. The composition of claim 1 or 2, wherein the lamellar particles are dispersed in compound B. 23. The composition of claim 22, wherein compound B is a copolymer of acrylonitrile-butadiene-styrene comprising functional groups for compatibility with polyamides. The styrene-maleimide copolymer according to claim 23, wherein the compound C comprises a styrene-maleimide copolymer comprising a functional group for compatibility with polyamide, a styrene-ethylene-butadiene-styrene or styrene-butadiene which represents a functional group for compatibility with polyamide. Composition selected from styrene block copolymers. 23. The composition of claim 22 wherein the functional group for compatibility with the polyamide is selected from maleic anhydride, carboxylic acid, or ester groups thereof. The composition of claim 23, wherein the functional group for compatibility with the polyamide is selected from maleic anhydride, carboxylic acid, or ester groups thereof. The composition of claim 23, wherein the weight ratio of Compound C and Compound D is as follows: Compound c: 5-20%        Compound D: 1-10%. 24. The composition of claim 23, wherein compound D is selected from ethylene-propylene rubber grafted with maleic anhydride. The method of claim 18, further comprising adding Compound A, which does not comprise Compound E, during operation b).