CN110872435A

CN110872435A - Transparent polyamide composition

Info

Publication number: CN110872435A
Application number: CN201811053466.2A
Authority: CN
Inventors: 杨选峰
Original assignee: Hubei Xingte Chemical Reagent Co Ltd
Current assignee: Hubei Xingte Chemical Reagent Co Ltd
Priority date: 2018-08-29
Filing date: 2018-08-29
Publication date: 2020-03-10

Abstract

A transparent polyamide composition, to a transparent polyamide composition highly resistant to chemical agents, to a process for its preparation and to articles obtained from said composition. The polyamide compositions according to the invention comprise from 1 to 99% by weight, preferably from 40 to 90% by weight, of a first polyamide consisting of aliphatic units containing at least 7 carbon atoms, isophthalic and terephthalic acids (the latter being predominantly) and cycloaliphatic diamine units, and from 99 to 1% by weight, preferably from 60 to 10% by weight, of a semi-crystalline polyamide consisting of at least 35% by weight, preferably 50% by weight, of aliphatic units containing at least 7 carbon atoms.

Description

Transparent polyamide composition

Technical Field

The present invention relates to a transparent polyamide composition, a process for its preparation and articles obtained from said composition.

Background

Polyamides and their alloys are widely used in a variety of applications. Some of these applications require special properties. Among these required properties, mention may be made of impact strength, tensile strength and/or compressive strength, i.e. mechanical strength. Other properties required are transparency and high resistance to chemical agents in order to withstand atmospheric effects over time. Many articles require a transparent appearance, high resistance to chemicals and good mechanical properties. For example, bottles, stoppers, spectacle frames and other items may be mentioned.

Therefore, there is a need today for transparent materials with high resistance to chemical agents.

Thus, a number of homopolyamides and copolyamides have been proposed, including amorphous and crystalline. Also, mixtures or alloys thereof are proposed. These alloys consist of a mixture of transparent amorphous copolyamides and crystalline (co) polyamides. The purpose of these alloys is to reduce production costs and/or to increase resistance to chemical agents.

In this way, JP-60-215053 and 60-215054 (publications) describe and claim an alloy which contains on the one hand a transparent polyamide and on the other hand a crystalline polyamide. The transparent polyamide comprises aliphatic units as the main monomer component, these units being selected from the group consisting of lauryllactam, 12-aminododecanoic acid or 11-aminoundecanoic acid, and cyclic units. The examples given for these transparent polyamides reveal a cycloaliphatic diamine, bis (4-aminocyclohexyl) methane, and an aromatic diacid, isophthalic acid, as cyclic units. These crystalline polyamides comprise polyamide-12 and/or-11, or copolyamides having 12 and/or 11 units as main monomer. Specific mixing conditions are not specified; it is merely indicated that any known method may be used. The resulting composition was transparent.

FR-A-2,575,756 and FR-A-2,606,416 describe and claim mixtures or alloys similar to the above. In both of these applications, isophthalic acid is also the major aromatic diacid component and no specific mixing conditions are specified. The resulting mixture or alloy is also transparent.

The mixtures of polyamides used in the above-cited documents meet the requirements of the products to be mixed. Thus, U.S. Pat. No. 4,4,404,317 describes mixing conditions for various polyamides, such as temperatures, which are particularly recommended not to exceed 300 ℃ since otherwise both crystalline and amorphous polyamides degrade. In particular, an injection moulding temperature of 230-305 ℃ and an extrusion temperature of 270-285 ℃ are specified in the annotation on the "technical data sheet" for the transparent polyamide Grilamid TR 55 comprising omega-dodecanoic lactam units, isophthalic acid as aromatic diacid and diamine A as cycloaliphatic diamine. Furthermore, it is known that the degradation temperature of crystalline polyamides, including polyamide 12 or polyamide 6/12, is about 270 ℃ and that both forming processes can be carried out in a very short time or in the presence of stabilizers at temperatures around 300 ℃. This is described on page 65 of the HULS "Engineering Thermoplastics" technical document.

On the other hand, EP-A-0,313,436 (in the name of the Applicant) describes ｃA transparent polyamide in which terephthalic acid is the main aromatic diacid component. The amorphous transparent polyamide has excellent performance in terms of mechanical properties and chemical resistance. Unfortunately, this amorphous transparent polyamide gives an opaque composition when mixed with a crystalline polyamide under the customary conditions described above.

Thus, if the desired alloy of the modified transparent polyamide is produced under normal conditions, the alloy is opaque and too high a temperature can lead to degradation of the polyamide.

Disclosure of Invention

The object of the present invention is to overcome the above-mentioned disadvantages of the prior art and to provide a transparent polyamide composition which can be carried out in a very short time or in the presence of stabilizers at temperatures of the order of 300 ℃.

The technical scheme of the invention is as follows: comprises the following components by weight: a) from 1 to 99%, preferably from 5 to 95%, of a first polyamide characterized by the following chain structure: in the formula: y1 and Y2 are numbers which together with Y1+ Y2 are between 10 and 200, and Y1/Y1+ Y2 is greater than or equal to 0.5; m, p, m ', p' are numbers equal to or greater than 0; z and Z 'in the aliphatic units-NH-Z-CO-and-NH-Z' -CO-may be the same or different and are either polymethylene segments- (CH2) n- (where n is an integer equal to or greater than 6, preferably an integer from 7 to 11) or a chain region containing amide groups resulting from the substantially stoichiometric condensation of one or more aliphatic diamines containing at least 4 carbon atoms between the two amine groups with one or more aliphatic dicarboxylic acids containing at least 4, preferably at least 6, carbon atoms between the two carboxyl groups; and-HN-R-NH-is a cycloaliphatic and/or aliphatic and/or araliphatic diamine; up to 30% of the aromatic dicarboxylic acids may be replaced by aliphatic dicarboxylic acids having more than 4, preferably 6, carbon atoms between the two carboxyl groups; b) 99-1%, preferably 95-5%, of a semi-crystalline polyamide comprising at least 30%, preferably 50%, by weight of aliphatic units defined by the chain block-NH- (CH2) n1-CO-, where n1 is an integer equal to or greater than 6, preferably from 7 to 11, optionally as part of a semi-aromatic unit, and/or aliphatic units defined by a chain block comprising amide groups resulting from the substantially stoichiometric condensation of one or more aliphatic diamines having at least 4 carbon atoms between two amine groups with one or more aliphatic dicarboxylic acids having at least 4, preferably at least 6, carbon atoms between two carboxyl groups; the composition comprises by weight: a) 40-90% of said first polyamide; and b) 60-10% of said semi-crystalline polyamide.

The semi-crystalline polyamide is selected from: PA12, PA11, corresponding copolymers, in which the content of units 12 or 11 is greater than 80% by weight, and mixtures thereof.

The polyamide is equivalent to L12/TA/IA/BMACM, and the molar ratio is as follows: 2-0.5/0.7-0.5/0.3-0.5/0.95-1.05.

The molecular weight of the polyamide is about 8,000-25,000, preferably 10,000-20,000.

The composition also contains fillers and/or additives.

A process for preparing a transparent polyamide composition comprising by weight: a)1 to 99%, preferably 5 to 95%, of a first polyamide characterized by the following chain structure; in the formula: y1 and Y2 are each independently thereof and Y1+ Y2 is a number from 10 to 200; m, p, m ', p' are numbers equal to or greater than 0; z and Z 'in the aliphatic units-NH-Z-CO-and-NH-Z' -CO-may be the same or different and are either polymethylene segments- (CH2) n- (where n is an integer equal to or greater than 6, preferably an integer from 7 to 11) or a chain region containing amide groups resulting from the substantially stoichiometric condensation of one or more aliphatic diamines containing at least 4 carbon atoms between the two amine groups with one or more aliphatic dicarboxylic acids containing at least 4, preferably at least 6, carbon atoms between the two carboxyl groups; and-HN-R-NH-is a cycloaliphatic and/or aliphatic and/or araliphatic diamine; up to 30% of the aromatic dicarboxylic acids may be replaced by aliphatic dicarboxylic acids having more than 4, preferably 6, carbon atoms between the two carboxyl groups, and b)99 to 1%, preferably 95 to 5%, of a semi-crystalline polyamide comprising at least 30%, preferably 50%, by weight of aliphatic units defined by the chain region-NH- (CH2) n1-CO-, where n1 is an integer equal to or greater than 6, preferably 7 to 11, optionally as part of a semi-aromatic unit, and/or aliphatic units defined by a chain region containing amide groups resulting from the substantially stoichiometric condensation of one or more aliphatic diamines having at least 4 carbon atoms between the two amine groups with one or more aliphatic dicarboxylic acids having at least 4, preferably at least 6, carbon atoms between the two carboxyl groups, characterized in that the process comprises the substitution at 250 ℃ and 350 ℃ in the presence of an amidation or transamidation catalyst Optionally in the form of a prepolymer having a degree of polymerization of at least 50%, with said semi-crystalline polymer.

The invention has the beneficial effects that: an ideal alloy for transparent polyamides is produced under normal conditions, and this alloy does not cause degradation of the polyamide even at high temperatures.

Drawings

Fig. 1 is a schematic structural view of the present invention.

Detailed Description

In FIG. 1, the invention relates to a transparent polyamide composition which is highly resistant to chemical reagents, comprising, by weight, a)1 to 99%, preferably 5 to 95%, of a first polyamide which is characterized by the following chain structure, wherein Y1 and Y2 are numbers, and Y1+ Y2 is between 10 and 200, and Y1/Y1+ Y2 is 0.5 or more, m, p, m ', p ' are numbers equal to or greater than 0, the aliphatic units-NH-Z-CO-and-NH-Z ' -CO-are identical or different, or are polymethylene segments- (CH2) n- (where n is an integer equal to or greater than 6, preferably 7 to 11) or are chain regions containing amide groups, which are derived from aliphatic diamines or diamines, which are derived from aliphatic diamines or from aliphatic diamines, preferably from aliphatic diamines, or from aliphatic diamine, preferably from aliphatic diamine, or from aliphatic diamine, which are derived from aliphatic diamine, preferably from aliphatic diamine, the invention, the following aliphatic diamine, the formula 1 to aliphatic diamine, or from aliphatic diamine, preferably from aliphatic diamine, or from aliphatic diamine, the aromatic diamine, or aliphatic diamine, preferably from aliphatic diamine, which is derived from aliphatic diamine, or from aliphatic diamine, the aromatic diamine, which is derived from aliphatic diamine, the aromatic diamine, or from aliphatic diamine, which is from aliphatic diamine, wherein the aromatic diamine, wherein Y1-diamine, wherein Y7, the aromatic diamine, wherein X7, the aromatic diamine, is equal to the aromatic diamine, or more than 0, is equal to the aromatic diamine, or to the aromatic diamine, is equal to the aromatic diamine, or more than 0, the aromatic diamine of the aliphatic diamine of the aromatic diamine of the aliphatic diamine of the aromatic diamine of the aliphatic chain of the aliphatic diamine of the formula, the aliphatic diamine of the formula, the aliphatic diamine of the formula, the aromatic diamine of the formula, the aliphatic diamine of the formula, the aromatic diamine of the formula, the aromatic diamine of the aliphatic diamine of the aromatic diamine of the aliphatic diamine of the formula, the aliphatic diamine of the aliphatic.

The term "araliphatic diamines" as used in the present invention refers to amines of the formula: H2N-R1-Ar-R2-NH2 wherein: r1 and R2, which may be the same or different, are straight or branched C1-C6 hydrocarbon groups; and Ar is a divalent aromatic group representing one aromatic ring or two or more aromatic rings linked by alkyl groups, which may also be substituted in any configuration, ortho, meta or para. It is contemplated that mixtures of araliphatic diamines may also be used in the present invention. For example, m-xylylenediamine (where Ar is m-phenyl and R1 is R2-CH 2-) may be mentioned. Saturated derivatives or those containing an ar-ester structure in their carbon chain are also contemplated as being provided in the present invention. For example, 1, 3-diaminomethylcyclohexane and 1, 3-diaminomethylnorbornene may be mentioned. It is contemplated that mixtures of aliphatic and/or cycloaliphatic and/or araliphatic diamines, especially the various isomers, may also be provided in the present invention. The expression "essentially in terms of theoretical quantities" means a diamine/diacid molar ratio of between 1.1/1 and 1/1.1. Thus, for example, the expression "substantially theoretical condensation reaction of one or more diamines and one or more diacids" may represent 6, 6 or 6, 12 units.

The expression "optionally as part of a semi-aromatic unit" as used in the present invention

Means that the aliphatic moieties in such semi-aromatic units are compatible; for example, for a polyamide 12-12, T having a weight composition of 50/50, the aliphatic unit represents 75% by weight of the polyamide. The term "transparent polyamide" as used in the present invention means that the polyamide has a transmittance of at least 70% when it is in the form of a sheet 2 mm thick. According to a particular embodiment of the invention, the composition comprises by weight: a) 40-90% of said first polyamide; and b) 60-10% of said semi-crystalline polyamide. Preferably, the composition comprises by weight: a) 50-80% of said first polyamide; and b) 50-20% of said semi-crystalline polyamide.

Said semi-crystalline polyamide comprises at least 80% by weight of aliphatic units defined by the chain segment-NH- (CH2) n1-CO-, where n1 is 7, 10 or 11, optionally as part of a semi-aromatic unit, and/or an aliphatic unit defined by the chain segment comprising amide groups resulting from the essentially theoretical amount-related condensation of one or more aliphatic diamines having at least 6 carbon atoms between two amine groups with one or more aliphatic dicarboxylic acids having at least 7 carbon atoms between two carboxyl groups. Preferably, said semi-crystalline polyamide is chosen from PA (Polyamide) 12, PA11, the corresponding copolymers in which the content of units 12 or 11 is greater than 80% by weight, and mixtures thereof. The semi-crystalline polyamide is PA12 and/or PA 11. The molecular weight of the semi-crystalline polyamide is about 10,000-30,000, preferably 15,000-25,000. The aliphatic units in the first polyamide are 12 and/or 11 units. The cycloaliphatic diamines have the following structural formula: in the formula: a and B, which may be the same or different, represent a hydrogen atom or a methyl group; x and Y, which may be the same or different, represent a hydrogen atom or a methyl group; q is an integer between 1 and 3; up to 50 mol% of these cycloaliphatic diamines may optionally be replaced by isophoronediamine. The cycloaliphatic diamine is bis (3-methyl-4-aminocyclohexyl) methane, up to 50 mol% of which may optionally be replaced by isophoronediamine. The compositions of the invention may contain conventional fillers, conventional additives, amidation or transamidation catalysts and other polymers, for example, other amorphous or semi-crystalline polyamides. Conventional fillers include, for example: inorganic fillers, such as talc, magnesium oxide, slag, kaolin, etc., especially glass fibers. Conventional additives are, for example, light and/or heat stabilizers, dyes, fluorescent whitening agents, plasticizers, mold release agents, flameproofing agents and others. The invention also relates to articles obtained from the compositions according to the invention, which can be produced by any known method, for example by injection moulding. The compositions of the invention are prepared by means of a novel process, another subject of the invention. The invention therefore also relates to a process for the preparation of a transparent polyamide composition highly resistant to chemical agents, comprising by weight: a) from 1 to 99%, preferably from 5 to 95%, of a first polyamide characterized by the following chain structure: in the formula: y1 and Y2 are numbers which together with Y1+ Y2 are between 10 and 200, and Y1/Y1+ Y2 is greater than or equal to 0.5; m, p, m ', p' are numbers equal to or greater than 0; z and Z 'in the aliphatic units-NH-Z-CO-and-NH-Z' -CO-may be the same or different and are either polymethylene segments- (CH2) n- (where n is an integer equal to or greater than 6, preferably an integer from 7 to 11) or a chain region containing amide groups resulting from the substantially stoichiometric condensation of one or more aliphatic diamines containing at least 4 carbon atoms between the two amine groups with one or more aliphatic dicarboxylic acids containing at least 4, preferably at least 6, carbon atoms between the two carboxyl groups; and-HN-R-NH-is a cycloaliphatic and/or aliphatic and/or araliphatic diamine; up to 30% of the aromatic dicarboxylic acids may be replaced by aliphatic dicarboxylic acids having more than 4, preferably 6, carbon atoms between the two carboxyl groups, and b)99 to 1%, preferably 95 to 5%, of a semi-crystalline polyamide comprising at least 30%, preferably 50%, by weight of aliphatic units defined by the chain block-NH- (CH2) n1-CO-, where n1 is an integer equal to or greater than 6, preferably 7 to 11, optionally as part of a semi-aromatic unit, and/or aliphatic units defined by a chain block containing amide groups resulting from the substantially stoichiometric condensation of one or more aliphatic diamines having at least 4 carbon atoms between the two amine groups with one or more aliphatic dicarboxylic acids having at least 4, preferably at least 6, carbon atoms between the two carboxyl groups, characterized in that the process comprises reacting the semi-crystalline polyamide with a mixture of at least one or more aliphatic dicarboxylic acids having more than 4, preferably 6, carbon atoms between the two carboxyl groups, preferably at a temperature of 300 ℃ to 400 ℃. The temperature of the mixing step is higher than the decomposition temperature of the polyamide, but, entirely surprisingly, this decomposition does not occur and a transparent polyamide composition is obtained which is highly resistant to chemical agents. According to a particular embodiment of the process of the invention, the temperature of the mixing step is between 300 ℃ and 370 ℃. The holding time at this temperature is from 1 second to 20 minutes, preferably from 10 seconds to 5 minutes.

Claims

1. A transparent polyamide composition characterized by: comprises the following components by weight: a) from 1 to 99%, preferably from 5 to 95%, of a first polyamide characterized by the following chain structure: in the formula: y1 and Y2 are numbers which together with Y1+ Y2 are between 10 and 200, and Y1/Y1+ Y2 is greater than or equal to 0.5; m, p, m ', p' are numbers equal to or greater than 0; z and Z 'in the aliphatic units-NH-Z-CO-and-NH-Z' -CO-may be the same or different and are either polymethylene segments- (CH2) n- (where n is an integer equal to or greater than 6, preferably an integer from 7 to 11) or a chain region containing amide groups resulting from the substantially stoichiometric condensation of one or more aliphatic diamines containing at least 4 carbon atoms between the two amine groups with one or more aliphatic dicarboxylic acids containing at least 4, preferably at least 6, carbon atoms between the two carboxyl groups; and-HN-R-NH-is a cycloaliphatic and/or aliphatic and/or araliphatic diamine; up to 30% of the aromatic dicarboxylic acids may be replaced by aliphatic dicarboxylic acids having more than 4, preferably 6, carbon atoms between the two carboxyl groups; b) 99-1%, preferably 95-5%, of a semi-crystalline polyamide comprising at least 30%, preferably 50%, by weight of aliphatic units defined by the chain block-NH- (CH2) n1-CO-, where n1 is an integer equal to or greater than 6, preferably from 7 to 11, optionally as part of a semi-aromatic unit, and/or aliphatic units defined by a chain block comprising amide groups resulting from the substantially stoichiometric condensation of one or more aliphatic diamines having at least 4 carbon atoms between two amine groups with one or more aliphatic dicarboxylic acids having at least 4, preferably at least 6, carbon atoms between two carboxyl groups; the composition comprises by weight: a) 40-90% of said first polyamide; and b) 60-10% of said semi-crystalline polyamide.

2. A transparent polyamide composition according to claim 1, characterized in that: the semi-crystalline polyamide is selected from: PA12, PA11, corresponding copolymers, in which the content of units 12 or 11 is greater than 80% by weight, and mixtures thereof.

3. A transparent polyamide composition according to claim 1, characterized in that: the polyamide is equivalent to L12/TA/IA/BMACM, and the molar ratio is as follows: 2-0.5/0.7-0.5/0.3-0.5/0.95-1.05.

4. A transparent polyamide composition according to claim 1, characterized in that: the molecular weight of the polyamide is about 8,000-25,000, preferably 10,000-20,000.

5. A transparent polyamide composition according to claim 1, characterized in that: the composition also contains fillers and/or additives.

6. A process for preparing a transparent polyamide composition comprising by weight: a)1 to 99%, preferably 5 to 95%, of a first polyamide characterized by the following chain structure; in the formula: y1 and Y2 are each independently thereof and Y1+ Y2 is a number from 10 to 200; m, p, m ', p' are numbers equal to or greater than 0; z and Z 'in the aliphatic units-NH-Z-CO-and-NH-Z' -CO-may be the same or different and are either polymethylene segments- (CH2) n- (where n is an integer equal to or greater than 6, preferably an integer from 7 to 11) or a chain region containing amide groups resulting from the substantially stoichiometric condensation of one or more aliphatic diamines containing at least 4 carbon atoms between the two amine groups with one or more aliphatic dicarboxylic acids containing at least 4, preferably at least 6, carbon atoms between the two carboxyl groups; and-HN-R-NH-is a cycloaliphatic and/or aliphatic and/or araliphatic diamine; up to 30% of the aromatic dicarboxylic acids may be replaced by aliphatic dicarboxylic acids having more than 4, preferably 6, carbon atoms between the two carboxyl groups, and b)99 to 1%, preferably 95 to 5%, of a semi-crystalline polyamide comprising at least 30%, preferably 50%, by weight of aliphatic units defined by the chain region-NH- (CH2) n1-CO-, where n1 is an integer equal to or greater than 6, preferably 7 to 11, optionally as part of a semi-aromatic unit, and/or aliphatic units defined by a chain region containing amide groups resulting from the substantially stoichiometric condensation of one or more aliphatic diamines having at least 4 carbon atoms between the two amine groups with one or more aliphatic dicarboxylic acids having at least 4, preferably at least 6, carbon atoms between the two carboxyl groups, characterized in that the process comprises the substitution at 250 ℃ and 350 ℃ in the presence of an amidation or transamidation catalyst Optionally in the form of a prepolymer having a degree of polymerization of at least 50%, with said semi-crystalline polymer.