HK1155470B - Polyamide moulding materials containing copolyamides for producing transparent moulding parts with low distorsion in climatic testing - Google Patents

Description

Polyamide moulding compounds containing copolyamides for producing transparent moulded parts with low distortion in climatic testing

Technical Field

The present invention relates to novel polyamide molding compositions which are characterized by significantly improved processability, in particular in the injection molding process, acceptable deformation in controlled climatic conditions tests, very good transparency, low haze, and even increased biomass.

The present invention therefore relates in particular to novel molding compositions based on transparent copolyamides, which are used for producing transparent moldings, in particular injection moldings with stringent technical requirements and high-quality surfaces, in particular in the visible region. The molding compositions of the invention also have high toughness, low water absorption and low deformation in the controlled climate conditions test. The invention relates in particular to novel molding compositions based on transparent copolyamides, based predominantly on monomers obtainable from renewable raw materials. The invention also relates to a process for the production of the polyamide molding composition and to moldings produced from the molding composition, such as mobile telephone casing materials or mobile telephone display screen materials, GPS equipment, MP3 players, spectacles, lenses, cameras, optics and telescopes.

It is particularly preferred that the moulding compositions according to the invention and the copolyamides present each comprise at least 50% by weight of biomass according to ASTM D6866-06A (with the term biomass in this document referring to the biobased content, see for example section 3.3.9, measurement of the content of nonfossilised, i.e.renewable carbon, see also chapter 17). The biomass in this context is derived from C¹²And C¹⁴Carbon isotope ratio of (a). This ratio is very different for fossil and renewable raw materials, so that a single measurement technique can be used to provide evidence for the biomass of the polyamide molding composition of the invention in a suitable form for unequivocally characterizing the product.

High quality surfaces are used to facilitate the "high end quality" positioning of automotive equipment, household equipment, consumer electronics, sports equipment, and easy-to-clean industrial surfaces. This places high demands on the material, which must not only have a high-quality appearance, but must also have crush resistance, flowability, ductility and low deformability. This requires low volume change due to crystallization and low hygroscopicity. In addition, excellent abrasion resistance and dynamic load capacity, which are typical characteristics of stretchable polyamides, are also required. Thus, moldings produced from the polyamide molding compositions of the invention have excellent transparency, toughness and abrasion resistance. These moldings have high chemical resistance and high bending fatigue resistance and can be used in harsh environments.

The moulding compositions according to the invention can be processed by known methods in known processing systems to give high-quality mouldings. As described above, the high-quality molded article can be used as a material for a mobile phone case or a mobile phone display screen, a GPS device, an MP3 player, spectacles, a lens, a camera, an optical device, a telescope, and the like.

For example, it is desirable to obtain ISO 14000 series Standard approvalThe certified user must accept economically sustainable requirements. For example, they propose CO on products₂Equilibrium life cycle analysis (life cycle assessment, LCA). In CO₂The short interval between release (source) and re-fixation (sink) is a contributing factor herein and can be achieved for the biomass of the invention by using a biorenewable raw material having the aforementioned values. The problem faced by the person skilled in the art is therefore that materials which are environmentally favourable must be used, but which hitherto involve unfavourable properties. To this end, one embodiment of the present invention provides teachings directed to eliminating the problems described, as it surprisingly provides an unexpectedly high quality transparent copolyamide material which is also substantially environmentally friendly as it is composed substantially of renewable raw materials.

Prior Art

Starting compounds or monomers for plastics are nowadays usually obtained from fossil sources (petroleum). However, these are limited resources, so alternative materials are being sought. Therefore, there is increasing interest in plastics that can be used to produce "bioplastics" or that have a high biomass. Molecular chains that can be compared to the properties of petroleum-based materials can now be produced by chemical processes of cracking and repolymerization. Examples of possible plant sources are plants which produce oleic, linoleic or linolenic acid or castor oil or tall oil fatty acids as examples of vegetable oils. For example, erucic acid can be obtained from seeds of rapeseed, mustard, wallflower or cress.

Renewable raw materials are therefore also a real alternative for the plastics industry, in particular because of global oil prices rising and energy shortages, and also because of political instability in oil producing countries.

Bioplastics have advantageous properties in many fields and therefore represent a real alternative to conventional fossil plastics. It is therefore reasonable to consider polyamides with a biomass of more than 50%. However, these polyamides are semi-crystalline polyamides having a glass transition temperature below 80 ℃ and also lack transparency. While typical semi-crystalline polyamides are still currently produced from petroleum-based monomers, examples of which are nylon-6, nylon-11, nylon-6, nylon-6, 9, nylon-6, 10, etc., in theory almost 100% biomass can be achieved in these materials.

In addition to the base materials, transparent polyamide molding compositions must also meet the stringent requirements of the customers, namely not only very good optical properties but also a high level of mechanical properties and chemical resistance. It is also required to pass a specified controlled climate environment test (see below).

DE 4310970A 1 describes transparent, amorphous polyamide molding compositions which have good stress cracking resistance and impact resistance and also have good resistance to alcohols, esters, ketones and boiling water, these compositions being obtained by polycondensation of aliphatic dicarboxylic acids with trans, trans-bis (4-aminocyclohexyl) methane (PACM) and, optionally, also with other diamines. However, the examples of DE 4310970A 1 relate only to the homopolyamides of PACM 10 and PACM 12. There is absolutely no disclosure of a diamine structure that gives a theoretically possible copolyamide using a second diamine different from the first diamine, nor is there any suggestion that the theoretical structure may have advantageous properties.

DE 10009756 a1 describes a polyamide compound having improved transparency and chemical resistance without sacrificing mechanical properties. The mixture comprises an amorphous or microcrystalline polyamide and a semi-crystalline polyamide, and also two different phosphorus additives. The chemical formula shown for amorphous or microcrystalline polyamides allows for a wide range of possible combinations of diamines and aliphatic dicarboxylic acids as starting components. However, no specific combination of two different diamines is described, nor of course any specific structure with specific properties (e.g. PA MACM 10/1010). The examples show amorphous polyamides based always on a combination of only one diamine (bis (4-amino-3-methylcyclohexyl) methane (MACM) with an aromatic dicarboxylic acid (isophthalic acid (IPS)) and lactam-12.

DE 2217016 a1 describes a PACM-based polyamide molding composition for producing polyamide fibers with improved dyeability and improved resistance to deformation at elevated temperatures. The PACM 10-12 polyamides described have microcrystalline or opaque systems, but these compositions are particularly desirable in the production of polyamide fibers, for example because of the desirable stretchability of the fibers. The polyamides described in DE 2217016, in particular the polyamide PACM 10-12, therefore provide moldings which have inadequate transparency and at the same time also exhibit high deformation in controlled climatic conditions.

EP-A-0001039 describes ｃA transparent polyamide obtained by polycondensation of positionally isomeric diaminocyclohexylmethane with optionally further diamines and pelargonic acid and optionally isophthalic acid and/or adipic acid.

Disclosure of Invention

It was therefore an object of the present invention to provide molding compositions based on transparent copolyamides and which can be used to produce transparent moldings, in particular transparent injection-molded moldings, which meet stringent technical requirements and have a high-quality surface ("high end quality"), in particular in the visible region, but which do not have the high glass transition temperatures, which are disadvantageous for processing, of the known transparent homopolyamides. The molding compositions have high toughness, low water absorption, low deformation, i.e.deformation of up to 4mm, in controlled climatic conditions testing, and improved processability, in particular in injection molding. Furthermore, it is another object that the material may be based on renewable raw materials.

The object is achieved according to the invention by a transparent copolyamide-based polyamide molding composition for producing transparent moldings, in particular transparent injection-molded moldings, which have high toughness, low water absorption, low deformation in a controlled-climate conditions test, in particular a deformation of the molding of at most 4mm, preferably at most 3mm, particularly preferably at most 2mm, in the controlled-climate conditions test, wherein the deformation of a sheet with dimensions of 100X 2mm under its own weight is determined at a temperature of 55 ℃ and a relative humidity of 95% in the controlled-climate conditions test, and one edge of the sheet is thus raised by 25mm and the deflection at the center of the sheet is measured (change in position after 168 hours relative to the initial conditions), wherein the molding composition comprises:

(A)40 to 100 wt% of at least one transparent copolyamide having a glass transition temperature (Tg) of at least 80 ℃ and at most 150 ℃, comprising:

-at least two diamines which are different from one another and are selected from compounds of (a) from 50 to 90 mol% of bis (4-amino-3-methylcyclohexyl) methane (MACM) and/or bis (4-amino-3-ethylcyclohexyl) methane (EACM) and/or bis (4-amino-3, 5-dimethylcyclohexyl) methane (TMACM) and (b) from 10 to 50 mol% of an aliphatic diamine having from 9 to 14 carbon atoms, in particular decamethylene diamine, preferably at least 20 mol% decamethylene diamine, in each case based on the total amount of diamines, and

one or more aliphatic dicarboxylic acids, in particular aliphatic dicarboxylic acids having 6 to 36 carbon atoms,

(B)0 to 60 wt.% of at least one other polymer selected from amorphous or semi-crystalline homo-or copolyamides, polyetheresteramides, polyetheramides, polyesteramides or mixtures thereof,

(C)0 to 10 wt.% of conventional additives selected from UV stabilizers, heat stabilizers, free-radical scavengers, and/or processing aids, inclusion inhibitors, lubricants, mold release aids, plasticizers, functional additives for influencing the optical properties, in particular the refractive index, impact modifiers, nanoscale fillers and/or other nanoscale materials, optical brighteners, dyes or mixtures thereof,

wherein the sum of components (A), (B) and (C) is 100 wt%.

The object is also achieved by a process for producing a polyamide molding composition as claimed in claim 12, wherein the polymer components (A) and (B) are produced in a known pressure vessel under pressure at 250 ℃ to 320 ℃ and subsequently under reduced pressure at 250 ℃ to 320 ℃ and subsequently evaporated at 260 ℃ to 320 ℃, and the polyamide molding composition is discharged in the form of strands, cooled, granulated and dried to give granules, components (A), optionally (B), optionally (C) are mixed in the form of granules, and molded in an extruder at a temperature of 220 ℃ to 350 ℃ to provide strands, cut by a suitable pelletizer to provide pellets, wherein during the mixing, additives required for modifying the molding composition, such as processing stabilizers, colorants, UV absorbers, heat stabilizers, flame retardants and other transparent polyamides or nylon-12 can be added.

Finally, the object is achieved by a molding as claimed in claims 13 to 16, obtainable from a polyamide molding composition as claimed in any of claims 1 to 11 by an injection molding process and an injection compression molding process at a melting temperature of 230 ℃ to 320 ℃, wherein after the material has been filled into the cavity, the mold temperature is set at 40 ℃ to 130 ℃ and optionally the mold is brought to apply compression to the hot molding at a temperature of 40 ℃ to 130 ℃.

The dependent claims comprise advantageous embodiments of the invention.

One embodiment of the molding compositions according to the invention has a biomass according to ASTM D6866-06 of at least 50% and a glass transition temperature of above 80 ℃ and up to 150 ℃. The transparency of 2mm thick sheets produced from the transparent molding composition was greater than 85% and the haze was at most 10%, measured by light transmission according to ASTM D1003. For the intended use of the molding compositions of the invention, high stiffness (tensile modulus of elasticity > 1300MPa) and high toughness (23 ℃ impact resistance: no fracture) are achieved. Low deformation in controlled climatic conditions tests is also achieved for the moldings produced from the molding compositions of the invention. In the controlled climate conditions test, a sheet having the dimensions 100X 2mm deflects (deforms) under its own weight to at most 4mm, preferably at most 3mm, particularly preferably at most 2mm, when the deflection is measured at the center of the sheet (55 ℃/95% relative humidity/duration: 168 hours).

The only monomers currently available based on natural raw materials are aliphatic monomers. In order to obtain transparent products, they must be combined with alicyclic, aromatic or branched monomer units. However, at least 50% of the required biomass requires a large amount of aliphatic components, as a result of which: first, the glass transition temperature (T)_g) Decrease in stiffness and light transmission (measured as transparency); second, the haze increases. One example which may be mentioned here is a PA10I/1010 type structure, which has a biomass of more than 50%. High concentrations of the 10I system (I ═ isophthalic acid) achieve T_gGreater than 80 ℃ and a transparency of over 90%, but a haze of 20% is outside the acceptable range for high quality optical applications.

Structures of the MACM10/1010 or MACM14/1014 type with biomass amounts of more than 50% are likewise preferred representatives of this class of copolyamides. The transparency was very good and the haze was acceptable. Realizable T_gWithin the framework of the structure of the invention: above 80 ℃ and up to 150 ℃.

Surprisingly, the inventors of the present application have found that MACM 6-36/6-366-36 copolyamides, MACM 9-18/9-149-18 copolyamides, preferably MACM 9-18/109-18 or MACM 10-14/1010-14 copolyamides, have the desired properties. For example, MACM10/1010 copolyamides with a MACM10 content of 66-46 mol% have a glass transition temperature of at least 89 ℃ and a biomass of 50-75%. The haze measured on 2mm thick sheets was below 5% and the light transmission was high, exceeding 93%. The gloss measured at an angle of 20 ° gives a very high value, about 150%. The gloss value rises above 100% in highly transparent materials because the lower surface also reflects light and this light adds to the light from the upper surface.

For the purposes of the present application, the light transmittance values used here as transparency measures are always values determined according to the ASTM D1003 method (CIE-C illuminant). In the experiments described below, the light transmission described herein was measured on 70 x 2mm discs or sheets of size 60 x 2mm using a Haze meter (Haze Guard Plus) of BYK Gardner (germany). The light transmittance values are suitable for the visible wavelength region defined in CIE-C, i.e. the fundamental wavelength range is from about 400 to about 770 nm. The 70X 2mm disks used here are produced, for example, in an Arburg injection molding machine using polishing abrasives, with a cylinder temperature of 200 ℃ to 340 ℃ and a mold temperature of 20 ℃ to 140 ℃.

Thus, the transparent copolyamides of the invention have the light transmission defined herein and have an amorphous or semi-crystalline morphology. The copolyamides of the invention are preferably polyamide systems which are processed in high molecular weight form free of other constituents to give transparent moldings in which the size of the crystallites is therefore smaller than the wavelength of visible light.

Furthermore, the MACM, TMACM and EACM based polyamides of the present invention are also highly transparent, with only low haze, throughout the claimed composition range.

The transparent copolyamides according to the invention preferably have a low enthalpy of fusion, i.e.a fusion enthalpy of < 5J/g.

Molded parts produced from the unreinforced molding compositions of the present invention exhibit stiffness characteristics of 1300 to 2000MPa elastic modulus, preferably 1500 to 2000MPa elastic modulus. The test specimens used for the measurement of notched impact value showed no fracture at room temperature (23 ℃) and-30 ℃.

Preferably, the polyamide component (a) is based on more than 50% of renewable raw materials. This is achieved by using predominantly, for example, azelaic acid, sebacic acid, tetradecyl diacid, C₃₆Dimerized fatty acids, aminoundecanoic acid, nonanediamine, decanediamine, and tetradecyldiamine, wherein these monomers are derived from various vegetable oils.

One important vegetable oil for monomer production is castor oil, which is obtained from african miracle (castor) tree seeds. The castor oil contains about 80-90% of ricinoleic acid triglyceride and other various C₁₈Glycerol esters of fatty acids. Castor oil has been used for thousands of years as a pharmaceutical, and is used in industrial oils, cosmetics, paints andhydraulic oil also has a long history. Sebacic acid is obtained by alkaline cleavage of castor oil at high temperature and subsequent treatment with hydrochloric acid. The pyrolytic decomposition of methyl ricinoleate gives heptaldehyde and methyl 10-undecanoate, which is converted into 11-aminoundecanoic acid by a plurality of reaction stages.

Azelaic acid and brassylic acid are also based on natural raw materials and they are produced by ozonolysis of oleic acid and erucic acid, respectively. Erucic acid is obtained from seeds of rape, mustard, wallflower or cress.

C₃₆Dimer acids via unsaturated C₁₈Thermal dimerization of carboxylic acids or esters thereof. Examples of starting materials are tall oil fatty acids and oleic or linolenic acid.

Nonanediamine, decanediamine and tridecanediamine are likewise based on natural starting materials since they are produced from the corresponding dicarboxylic acids, for example by the dinitrile route.

There are other raw materials of increasing industrial importance which are obtained, for example, by microbial fermentation, which can likewise be used.

A particularly preferred feature of the transparent copolyamide (A) is therefore that it has a biomass according to ASTM D6866-06a of at least 54% by weight or at least 58% by weight. Particular preference is given to a biomass of at least 60% by weight or at least 65% by weight, in particular in the range from 50 to 75% by weight.

In order for the polyamide molding compositions of the invention to have the above-claimed properties, the concentration of cycloaliphatic diamines must in particular be in the range from 5 to 80 mol%, preferably from 55 to 75 mol%, particularly preferably from 60 to 75 mol%, based on the total diamine content. According to the invention, the concentration of aliphatic diamines, in particular 1, 10-decamethylenediamine, is always at least 20 mol%, preferably at least 32 mol%, based on the total diamine content, preferably in the range from 25 to 45 mol%, very preferably in the range from 25 to 40 mol%, based on the total diamine content.

The invention uses 50 to 90 mol% of bis (4-amino-3-methylcyclohexyl) methane (MACM) and/or bis (4-amino-3-ethylcyclohexyl) methane (EACM) and/or bis (4-amino-3, 5-dimethylcyclohexyl) methane (TMACM) and/or bis (4-amino-3, 5-dimethylcyclohexyl) propane and 10 to 50 mol% of at least one aliphatic diamine having 9 to 14 carbon atoms, particularly preferably having 10 to 14 carbon atoms, in particular decamethylenediamine, in each case based on the total amount of diamines. The present invention preferably uses aliphatic diamines, such as 1, 9-nonanediamine, 1, 10-decanediamine, 1, 11-undecanediamine, 1, 12-dodecanediamine, 1, 13-tridecanediamine or 1, 14-tetradecanediamine, and particularly preferably uses at least 20, 30, 50 or 100 mol% of decanediamine as aliphatic diamine, based on the total content of aliphatic diamines.

The expression PACM used in the present application denotes the ISO name bis (4-aminocyclohexyl) methane, which is commercially available as Dicykan 4, 4' -diaminodicyclohexylmethane (CAS number 1761-71-3). The expression MACM denotes the ISO name bis (4-amino-3-methylcyclohexyl) methane, which is commercially available as Laromine C2603, 3 '-dimethyl-4, 4' -diaminodicyclohexylmethane (CAS number 6864-37-5). The expressions EACM and TMACM denote bis (4-amino-3-ethylcyclohexyl) methane (EACM) and/or bis (4-amino-3, 5-dimethylcyclohexyl) methane (TMACM).

For the purposes of the present invention, the expressions PACM, MACM, EACM and TMACM are intended to include all common names, trade names, other names familiar to those skilled in the art corresponding to the chemical structures of the above-mentioned compounds.

The aliphatic dicarboxylic acids preferably have from 10 to 36 carbon atoms, in particular from 10 to 18 carbon atoms.

The aliphatic dicarboxylic acids used preferably include those selected from the group consisting of azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid, tetradecanedioic acid, pentadecanedioic acid, hexadecanedioic acid, heptadecanedioic acid, octadecanedioic acid, C₃₆Acids of dimerized fatty acids and mixtures thereof, in particular aliphatic diacids, containing at least 20 mol%, preferably at least 30 mol%, particularly preferably at least 50 mol%, of fatty acidsMole% of sebacic acid, based on the total amount of dicarboxylic acids, and wherein the aliphatic diacid is particularly preferably sebacic acid only.

The copolyamide (A) is characterized in particular by a chain having the following formula (I):

(MACMX)_x/(10Y)_y/LC_z (I)

wherein the definition is as follows:

x and Y are aliphatic dicarboxylic acids having 9 to 18 and 36 carbon atoms,

x is 25 to 90 mol%,

y represents 5 to 50 mol%,

10-1, 10-decanediamine,

LC-lactams and/or amino acids having 6 to 12 carbon atoms,

z is 0 to 50 mol%,

wherein x + y + z is 100 mol%,

and X, 10Y and LC represent a total content of at least 50 wt%. If X, Y and LC are based on renewable feedstocks, the total wt% of X, 10Y, and LC is biomass.

The component MACMX used alone or in mixtures in formula (I) comprises amorphous units, for example of the type MACM9, MACM10, MACM11, MACM12, MACM13, MACM14, MACM15, MACM16, MACM17, MACM18, MACM 36. The aliphatic dicarboxylic acids having 9 to 18 or 36 carbon atoms are preferably produced from non-petroleum based renewable raw materials. The diamine MACM may be replaced in whole or in part by bis (4-aminocyclohexyl) methane or other alkyl-substituted derivatives of bis (4-amino-3-ethylcyclohexyl) propane, in particular by bis (4-amino-3-ethylcyclohexyl) methane (EACM) and/or bis (4-amino-3, 5-dimethylcyclohexyl) methane (TMACM) and/or bis (4-amino-3-methylcyclohexyl) propane.

Component 10Y used in formula (I) comprises semi-crystalline units, for example of the PA 109, PA1010, PA 1011, PA1012, PA 1013, PA1014, PA 1015, PA 1016, PA 1017, PA 1018, PA 1036 type, used alone or in mixture. Preferably the components are produced from non-petroleum based renewable feedstocks.

Particularly preferred copolyamides (A) according to the invention are therefore MACM9/109, MACM10/1010, MACM12/1012 and MACM 14/1014.

The component LC used in formula (I) comprises lactam 11 and lactam 12 and alpha, omega-amino acids having 10 to 12 carbon atoms or mixtures thereof. Lactams and aminoundecanoic acids from renewable raw materials are preferred.

Glass transition temperature (T) of copolyamide (A)_g) At least 80 ℃, preferably at least 85 ℃, in particular at least 90 ℃ or 100 ℃. On the other hand, the glass transition temperature (T) of the copolyamide (A)_g) At most 150 ℃, preferably at most 135 ℃, particularly preferably at most 125 ℃. Therefore, the preferred glass transition temperature (T) of component (A)_g) Is 80 to 135 ℃, or 90 to 135 ℃, or 100 to 135 ℃, especially 85 to 125 ℃.

The T is_gRanges are obtained in combination with cycloaliphatic systems, such as MACM10 or MACM12, and when the ratio is sufficiently large, the copolyamide (A) is replaced by an aliphatic component, such as PA1010 or PA1012, as described above. The reduced glass transition temperature (T) of the invention compared with homopolymers based on cycloaliphatic diamines_g) Higher flowability and thus better processability of the polymer melt of the invention is provided. The polyamide molding compositions of the invention cure at a slower rate (compared to homopolyamide molding compositions) and therefore injection molding provides better surface quality (smoother surface) and higher weld line strength by avoiding flowlines and other artifacts. Furthermore, the copolyamides of the invention are also produced and processed under milder conditions, i.e. at lower temperatures (10 ℃ C. to 30 ℃ C.), so that the moldings produced therefrom have significantly fewer inclusions (originating from the polycondensation process) and significantly less discoloration, which is of particular importance for transparent materials and their use in the optical field.

The component (B) used comprises other polymers, preferably amorphous or semi-crystalline polyamides or copolyamides of the following formula (II):

(MACMX)_x/(PACMY)_y/(MXDV)_v/LC_z (II)

wherein the definition is as follows:

x, Y and V aliphatic dicarboxylic acids having 9 to 18 and 36C atoms and terephthalic acid (T) and isophthalic acid (I) and mixtures thereof,

x＝0～100wt％，y＝0～100wt％，v＝0～100wt％，

LC-lactams and/or amino acids (S) having 6 to 12 carbon atoms,

z＝0～100wt％，

v+x+y+z＝100wt％。

representative preferred examples of such component (B) are the following polyamides or copolyamides: MACM10, MACM12, MACM14, MACMI/12, MACMI/MACMT/12, MACMI/PACMT/12, PA11, PA12, wherein I is isophthalic acid and T is terephthalic acid.

The other polymer (component (B)) may also be selected from polyetheresteramides, polyetheramides, polyesteramides and mixtures thereof. The copolymer may have a random, alternating or block structure. The polyamide component here is preferably based on PA6, PA66, PA69, PA610, PA612, PA99, PA1010, PA1012, PA1014, PA11, PA12 polyamides or mixtures thereof. Polyamides of the following types are preferred: PA1010, PA11, and PA 12. The polyester component of the copolymer is a diol or diamine based on polyethylene glycol and/or polypropylene glycol and/or polybutylene glycol. The ester component or polyester component is based on a polyester of an aliphatic and/or aromatic dicarboxylic acid and an aliphatic diol, preferably on a dimerized fatty acid diol.

The polyamide molding composition of the invention preferably comprises:

55 to 100 wt% of component (A),

0 to 45 wt% of component (B),

0 to 5 wt% of component (C),

and particularly preferably comprises:

65 to 90 wt% of component (A),

10 to 35 wt% of component (B),

0 to 5 wt% of component (C).

The polyamide molding compositions of the invention may, however, comprise customary additives (component (C)) in small proportions (less than 10% by weight, preferably less than 5% by weight, particularly preferably less than 3% by weight). Therefore, the concentration of the additive (component (C)) is preferably 0.01 to 5 wt%, particularly 0.3 to 3 wt%. The additives mentioned may be stabilizers, for example uv stabilizers, heat stabilizers or radical scavengers, and/or may be processing aids, inclusion inhibitors, lubricants, mold release aids or plasticizers, and/or may be functional additives, preferably for influencing the optical properties, in particular the refractive index, and/or may be combinations or mixtures thereof. The molding compositions may also comprise (as component (C)) nanoscale fillers and/or nanoscale functional materials, for example refractive index-increasing layered minerals or metal oxides or optical brighteners or dyes, for example photochromic dyes.

For the purposes of the present invention, the molding compositions may also comprise fillers and/or other materials familiar to those skilled in the art, for example: glass fibers, glass beads, carbon fibers, carbon black, graphite, flame retardants, minerals such as titanium dioxide, calcium carbonate or barium sulfate, or for example impact modifiers such as functionalized polyolefins.

Preferred impact modifiers are selected from acid-modified ethylene-alpha-olefin copolymers, ethylene-glycidyl methacrylic acid copolymers and methacrylate-butadiene-styrene copolymers.

However, the moulding compositions according to the invention may also receive other fillers or reinforcing agents. In this case, the moldings produced from the molding compositions are naturally opaque. Reinforcing agents that can be used are not only glass fibers and carbon fibers, but in particular those based on renewable raw materials and over 50% biomass. Particular preference is given to using natural fibers such as cellulose fibers, hemp fibers, flax fibers, cotton fibers, wool fibers or wood fibers.

The polymer components (A) and (B) are produced in known pressure vessels. Firstly, the pressurizing stage is carried out at 250-320 ℃. Then, the pressure is reduced at 250 to 320 ℃. Devolatilization is carried out at 260-320 ℃. The polyamide molding composition is then discharged in the form of strands, cooled in a water bath at from 5 ℃ to 80 ℃ and granulated. The granules were dried at 80 ℃ for 12 hours to a moisture content of less than 0.06%. Additives such as lubricants, dyes, stabilizers, etc. may be applied to or sintered onto the particles during the drying process while the particles are being recycled.

In order to set the desired relative viscosity (components (A) and (B)), i.e.1.45 to 2.30, preferably 1.55 to 2.00, particularly preferably 1.60 to 1.90, measured in a 0.5% strength by weight solution in m-cresol, a diamine or dicarboxylic acid can be used in a slight excess of 0.01 to 2 mol%. Preferably, 0.01 to 2.0 wt.%, preferably 0.05 to 0.5 wt.%, of a monoamine or monoacid is used for the conditioning. Suitable regulators are benzoic acid, acetic acid, propionic acid, octadecylamine or mixtures thereof. Particular preference is given to regulators having amino or carboxylic acid groups, which additionally comprise HALS-type or tert-butylphenol-type stabilizers, for example triacetonediamine or bistripropylenediamine derivatives of isophthalic acid.

Suitable catalysts for accelerating the polycondensation reaction are phosphorus-containing acids such as H₃PO₂、H₃PO₃Or H₃PO₄Their salts or organic derivatives, wherein they simultaneously reduce discoloration during processing. The amount of the catalyst added is 0.01 to 0.5 wt%, preferably 0.03 to 0.1 wt%. Suitable antifoams for avoiding foaming during devolatilization are siloxanes or siloxane derivatives, forThe amount of 10% emulsion is O.O1-1. Owt%, preferably 0.01-0.10 wt%.

A suitable heat stabilizer or a suitable uv stabilizer may be added to the mixture in an amount of o.o1 to 0.5 wt% before the polycondensation process. The high melting point type is preferably used. Irganox1098 is particularly preferably used.

The transparent molding compositions of the invention can be provided with additives such as stabilizers, lubricants such as paraffin oil or stearates, dyes, fillers, impact modifiers such as ethylene-glycidyl methacrylate terpolymers, preferably in the refractive index range of the molding compositions of the invention, or maleic anhydride-grafted polyethylene or polypropylene, or reinforcing materials such as glass fibers or glass beads, or nanoparticles, for example, which provide transparent dispersions, or mixtures of the additives, by means of known mixing processes, in particular extrusion in single-or multi-screw extruders, using melting temperatures of from 250 ℃ to 350 ℃.

Suitable processes for producing highly transparent moldings from the transparent polyamide molding compositions of the invention are injection molding processes or injection compression processes at melt temperatures of from 230 ℃ to 320 ℃, where the mold temperature is set to from 40 ℃ to 130 ℃ and, optionally, after the material has been filled into the cavity, compression is applied to the hot moldings using a mold having a temperature of from 40 ℃ to 130 ℃. The stretch injection compression molding process is a particularly suitable process for producing defect-free, low-stress molding surfaces from the transparent polyamide composition of the invention, such as spectacle lenses or high-quality casing parts; in this process, the cavity is filled with material to have a wall thickness of 1-5 mm, and while the mold cavity is enlarged, the material continues to be filled to provide a higher wall thickness.

Suitable processes for producing foils, tubes and semi-finished products in single-layer or multilayer form from the transparent polyamide molding compositions according to the invention are extrusion processes using melt temperatures of from 250 ℃ to 350 ℃ in single-screw or multi-screw extruders, where suitable adhesion promoters in the form of suitable copolymers or blends can be used to achieve compatibility of the layers.

The mouldings composed of the transparent polyamide moulding compositions according to the invention can be joined to one another by the customary processes, such as ultrasonic welding, incandescent filament welding, friction welding, spin welding or laser welding modified by means of laser-active dyes having an absorption range of 800nm to 2000 nm.

Suitable processes for producing hollow bodies and bottles in the form of a single layer or of multiple layers from the transparent polyamide molding compositions according to the invention are injection blow molding processes, injection stretch blow molding processes and extrusion blow molding processes.

The molding compositions of the invention can also be processed to foils, such as flat foils, blown foils, cast foils or multilayer foils. Preferred methods for further processing the foil are lamination, in-mold coating, stretching, orientation, printing or dyeing.

The mouldings can be dyed in bulk using known dipping methods or in a subsequent process. The molded parts are further processed, where appropriate, by rolling, drilling, grinding, laser marking, laser cutting and/or laser welding.

Suitable uses of the moldings composed of the transparent polyamide molding compositions according to the invention are the viewing windows of direct oil-contact heating systems, filter cups for drinking water treatment, baby bottles, carbonizers, crockery, gas or liquid flowmeters, bell housings, watch cases and lamp housings and reflectors for automobiles.

The following examples will serve to illustrate the invention without limiting it.

Examples

The polyamide molding compositions according to the invention were prepared in a known laboratory autoclave having a capacity of 130L. The pressurization phase is first carried out at 290 ℃. Followed by a reduction in pressure at 280 ℃. The devolatilization was carried out at 280 ℃. The polyamide molding composition is then discharged in the form of strands, cooled in a water bath and granulated. The granules were dried at 80 ℃ for 12 hours to a moisture content of less than 0.06%. Using the transparent polyamide molding compositions according to the invention, highly transparent moldings or corresponding test specimens are produced in an Arburg 420C Allrounder 1000-250 injection molding machine at melt temperatures of from 250 ℃ to 280 ℃ with the mold temperature being adjusted to 60 ℃. The rotating speed of the screw is 150-400 rpm.

The materials or moldings produced have the properties listed in tables 1 and 2 below.

TABLE 1

TABLE 2

n.d.: not determined

The glass transition temperatures of the transparent homopolyamides MACM10 and MACM12 are 165 ℃ and 155 ℃ respectively, and the melt viscosities of the transparent homopolyamides MACM10 and MACM12 are 15-22 cm³The viscosity (relative viscosity) of the solution is 1.85-1.80 in 10 minutes (MVR, 275 ℃/5 kg). The copolyamides of the invention have a significantly lower melt viscosity at the same relative viscosity and are therefore easier to process when compared with known homopolyamides. The deformation (0.6mm) of the moldings of example 1 according to the invention in the controlled-climate test was only slightly greater than that of the moldings made from homopolyamide MACM10 (deformation 0.5 mm).

The aliphatic component of the copolyamide of the invention (inventive examples 1, 4 and 5) allows a further reduction in the water content compared to the transparent homopolyamide MACM 10: 1.20 at 23 ℃ and 50% relative humidity.

The relative viscosity (. eta.) is determined in a 0.5% strength by weight solution in m-cresol at 20 ℃ according to DIN EN ISO 307_rel)。

Determination of the glass transition temperature (T) according to ISO 113571/2_g) Melting Point (T)_m) And enthalpy of fusion (H)_m). Differential Scanning Calorimetry (DSC) was performed at a temperature rise rate of 20K/min.

The tensile modulus of elasticity, ultimate tensile strength and tensile strain at break were determined according to ISO 527 on ISO tensile specimens (standard: ISO/CD3167, type A1, 170X 20/10X 4mm, temperature 23 ℃) using a tensile test speed of 1 mm/min (tensile modulus of elasticity) or 50 mm/min (ultimate tensile strength, tensile strain at break).

Impact and notched impact resistance were measured according to ISO 179/keU using the Charpy impact method on ISO test specimens (standard: ISO/CD3167, type B1, 80X 10X 4mm, at-30 ℃ and 23 ℃).

Light transmittance (clarity) and haze were measured according to ASTM D1003 on sheets of size 2X 60mm or discs of size 2X 70mm using a Byk gardner haze Meter and CIE illuminant C at a temperature of 23 ℃. The transmittance value is expressed as% of the amount of incident light.

Gloss was measured according to EN ISO 2813 at a temperature of 23 ℃ on discs with dimensions 70X 2mm using a Minolta Multi Gross 268 at angles of 20 ℃ and 60 ℃.

The controlled climate conditions test was used to determine the deflection under its own weight of a sheet of dimensions 100 x 2mm at a temperature of 55 ℃ and a relative humidity of 95%. For this purpose, one edge of the sheet was raised by 25mm, and the deformation at the center of the sheet (change in position from the initial condition) was measured after 168 hours.

MVR (melt volume flow) was determined according to ISO 1133 at 275 ℃ and 5kg load.

The present invention therefore provides novel polyamide molding compositions which are characterized by significantly improved processability, in particular in the injection molding process, acceptable deformation in controlled climatic conditions tests, very good transparency, low haze, even with increased biomass.

Claims (28)

1. A transparent copolyamide-based polyamide molding composition for producing transparent moldings, comprising:

(A)40 to 100 wt.% of at least one transparent copolyamide having a glass transition temperature (T)_g) At least 80 ℃ and at most 150 ℃, comprising:

-at least two diamines which are different from one another and are selected from the group consisting of (a) from 50 to 90 mol% of bis (4-amino-3-methylcyclohexyl) methane (MACM) and/or bis (4-amino-3-ethylcyclohexyl) methane (EACM) and/or bis (4-amino-3, 5-dimethylcyclohexyl) methane (TMACM) and (b) from 10 to 50 mol% of a mixture of aliphatic diamines having from 9 to 14 carbon atoms, in each case based on the total amount of diamines, and

-one or more aliphatic dicarboxylic acids,

(B)0 to 60 wt.% of at least one other polymer selected from amorphous or semi-crystalline homo-or copolyamides, polyetheresteramides, polyetheramides, polyesteramides or mixtures thereof,

(C)0 to 10 wt.% of conventional additives selected from UV stabilizers, heat stabilizers, radical scavengers, and/or processing aids, inclusion inhibitors, lubricants, mold release aids, plasticizers, functional additives for influencing optical properties, impact modifiers, nanoscale fillers and/or other nanoscale materials, optical brighteners, dyes or mixtures thereof,

wherein the sum of components (A), (B) and (C) is 100 wt%.

2. Transparent copolyamide-based polyamide molding composition according to claim 1, characterized in that it is used for producing injection-molded parts with high toughness, low water absorption, low deformation in controlled climate conditions testing.

3. Transparent copolyamide-based polyamide molding composition according to claim 2, characterized in that it has a deformation of at most 4mm in the controlled climate conditions test, in which the deflection under its own weight of a sheet of dimensions 100 x 2mm is determined at a temperature of 55 ℃ and a relative humidity of 95%, for which purpose one edge of the sheet is raised by 25mm, and the deformation at the center of the sheet, i.e. the change in position relative to the initial conditions, is measured after 168 hours.

4. Transparent copolyamide-based polyamide molding composition according to claim 1, characterised in that the molding composition comprises:

(A)40 to 100 wt% of at least one transparent copolymerPolyamides, their glass transition temperatures (T)_g) At least 80 ℃ and at most 150 ℃, comprising:

-at least two diamines which are different from one another and are selected from (a) from 50 to 90 mol% of bis (4-amino-3-methylcyclohexyl) methane (MACM) and/or bis (4-amino-3-ethylcyclohexyl) methane (EACM) and/or bis (4-amino-3, 5-dimethylcyclohexyl) methane (TMACM) and (b) from 20 to 50 mol% of decadiamine, in each case based on the total amount of diamines, and

one or more aliphatic dicarboxylic acids having 6 to 36 carbon atoms,

(B)0 to 60 wt.% of at least one other polymer selected from amorphous or semi-crystalline homo-or copolyamides, polyetheresteramides, polyetheramides, polyesteramides or mixtures thereof,

(C)0 to 10 wt.% of conventional additives selected from the group consisting of UV stabilizers, heat stabilizers, radical scavengers, and/or processing aids, inclusion inhibitors, lubricants, mold release aids, plasticizers, functional additives for influencing the optical properties, i.e. the refractive index, impact modifiers, nanoscale fillers and/or other nanoscale materials, optical brighteners, dyes or mixtures thereof,

wherein the sum of components (A), (B) and (C) is 100 wt%.

5. Polyamide molding composition based on transparent copolyamides according to claim 1, where the copolyamide is predominantly based on monomers available from renewable raw materials and where the biomass according to ASTM D6866-068a of copolyamide (a) and/or other component (B) is at least 50 wt%.

6. Polyamide molding composition based on transparent copolyamides according to claim 1, where the copolyamide is based predominantly on monomers available from renewable raw materials and where the biomass according to ASTM D6866-068a of copolyamide (a) and/or other component (B) is 50-75 wt%.

7. A transparent copolyamide-based polyamide molding composition according to any one of claims 1-6, characterised in that the concentration of cycloaliphatic diamine is 50 to 80 mol% and the aliphatic diamine is used in a concentration of 25 to 45 mol% of the total diamine.

8. Polyamide molding composition according to any one of claims 1 to 6, characterized in that the concentration of cycloaliphatic diamines is from 55 to 75 mol% based on the total amount of diamines and the aliphatic diamines is used in a concentration of from 25 to 45 mol% based on the total amount of diamines.

9. The transparent copolyamide-based polyamide molding composition according to any one of claims 1 to 6, wherein the aliphatic dicarboxylic acid is selected from azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid, tetradecanedioic acid, pentadecanedioic acid, hexadecanedioic acid, heptadecanedioic acid, octadecanedioic acid, C₃₆Dimerized fatty acids and mixtures thereof.

10. The transparent copolyamide-based polyamide molding composition according to any one of claims 1 to 6, wherein the aliphatic dicarboxylic acid is selected from azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid, tetradecanedioic acid, pentadecanedioic acid, hexadecanedioic acid, heptadecanedioic acid, octadecanedioic acid, C₃₆Dimer fatty acids and mixtures thereof, wherein the aliphatic dicarboxylic acid comprises at least 20 mole% sebacic acid.

11. Polyamide molding composition according to any one of claims 1 to 6, characterized in that the aliphatic dicarboxylic acid is solely sebacic acid.

12. Transparent copolyamide-based polyamide molding composition according to any one of claims 1 to 4, in which copolyamide (A) is characterized by a chain of formula (I):

(MACMX)_x/(10Y)_y/LC_z (I)

wherein the definition is as follows:

x and Y are aliphatic dicarboxylic acids having 9 to 18 and 36 carbon atoms,

x is 25 to 90 mol%,

y represents 5 to 50 mol%,

LC-lactams and/or amino acids having 6 to 12 carbon atoms,

z is 0 to 50 mol%,

wherein x + y + z is 100 mol%,

and X, 10Y and LC represent a total content of at least 50 wt%.

13. Transparent copolyamide-based polyamide molding composition according to claim 12, in which the component MACMX used in formula (I) contains amorphous units selected from MACM9, MACM10, MACM11, MACM12, MACM13, MACM14, MACM15, MACM16, MACM17, MACM18, MACM36 or mixtures thereof, where the diamine MACM can be replaced in whole or in part by bis (4-amino-3-ethylcyclohexyl) methane (EACM) and/or bis (4-amino-3, 5-dimethylcyclohexyl) methane (TMACM) and/or bis (4-amino-3-methylcyclohexyl) propane.

14. A transparent copolyamide-based polyamide molding composition according to claim 12, characterised in that component 10Y used in formula (I) contains the type of semi-crystalline units from PA 109, PA1010, PA 1011, PA1012, PA 1013, PA1014, PA 1015, PA 1016, PA 1017, PA 1018 and PA 1036, alone or in mixture.

15. A transparent copolyamide-based polyamide molding composition according to claim 12, where component LC of formula (I) is selected from the group consisting of lactam 11, lactam 12 and α, ω -amino acids having 10 to 12 carbon atoms or mixtures thereof.

16. Transparent copolyamide-based polyamide molding composition according to any one of claims 1 to 4, characterised in that the copolyamide (A) has a glass transition temperature of at least 85 ℃.

17. Polyamide molding composition according to any of claims 1 to 4, characterized in that the copolyamide (A) has a glass transition temperature of from at least 100 ℃ to 135 ℃.

18. The transparent copolyamide-based polyamide molding composition according to any one of claims 1 to 4, wherein the copolyamide (A) is selected from MACM9/109, MACM10/1010, MACM12/1012 and MACM 14/1014.

19. A transparent copolyamide-based polyamide molding composition according to any one of claims 1 to 4, characterised in that the polyamide molding composition comprises a blend of component (A) and a second polymer, component (B), and the component (B) used comprises a polymer which is an amorphous or semi-crystalline polyamide or copolyamide, characterised by having chains of the following formula (II):

(MACMX)_x/(PACMY)_y/(MXDV)_v/LC_z (II)

wherein the definition is as follows:

x, Y and V aliphatic dicarboxylic acids having 9 to 18 and 36C atoms and terephthalic acid (T) and isophthalic acid (I) and mixtures thereof,

x＝0～100wt％，y＝0～100wt％，v＝0～100wt％，

LC-amino acids (S) having 6 to 12C atoms and/or lactams,

z＝0～100wt％，

v+x+y+z＝100wt％。

20. a process for producing a transparent copolyamide-based polyamide molding composition according to any one of claims 1 to 19, characterised in that the polymer components (a) and (B) are produced in a known pressure vessel using the following steps: a pressurizing stage at 250-320 ℃; then decompressing at 250-320 ℃; followed by devolatilization at from 260 ℃ to 320 ℃ and discharge of the polyamide molding composition in the form of strands, cooling, granulation and subsequent drying of the granules, mixing of component (A) and optionally component (B) and optionally component (C) in the form of granules and molding in an extruder having a melt temperature of from 220 ℃ to 350 ℃ to give strands, cutting with a suitable pelletizer to give granules.

21. Process for the production of a transparent copolyamide-based polyamide molding composition according to claim 20, wherein polymer components (A) and (B) are produced in a known pressure vessel by the following steps: a pressurizing stage at 250-320 ℃; then decompressing at 250-320 ℃; followed by devolatilization at from 260 ℃ to 320 ℃ and discharge of the polyamide molding composition in the form of strands, cooling, granulation and subsequent drying of the granules, mixing of component (A) and optionally component (B) and optionally component (C) in the form of granules and molding in an extruder having a melt temperature of from 220 ℃ to 350 ℃ to give strands, cutting with a suitable granulator to give granules, wherein during the mixing process the additives required for modifying the molding composition are added, the additives being selected from the group consisting of processing stabilizers, colorants, UV absorbers, heat stabilizers, flame retardants and other transparent polyamides or nylon-12.

22. A molded part obtained from the polyamide molding composition as claimed in any of claims 1 to 19 by an injection molding process and an injection compression molding process at a melt temperature of from 230 ℃ to 320 ℃, wherein the mold temperature is set to from 40 ℃ to 130 ℃, and optionally, after the material has been filled into the cavity, the hot molded part is compressed with the mold having a temperature of from 40 ℃ to 130 ℃.

23. The molded object of claim 19 wherein the light transmission is determined according to ASTM D1003 on sheets of size 2 x 60mm or discs of size 2 x 70mm at a temperature of 23 ℃ by using a haze meter of Byk gardner from CIE illuminant C, wherein the light transmission is at least 85%.

24. The molded object of claim 22 wherein the light transmission is determined according to ASTM D1003 on sheets of size 2 x 60mm or discs of size 2 x 70mm at a temperature of 23 ℃ by using a haze meter of Byk gardner from CIE illuminant C, wherein the light transmission is at least 90%.

25. The molded object according to claim 22, wherein the haze, measured according to astm d1003, for a sheet of 2mm thickness made from the polyamide molding composition according to any one of claims 1 to 19 is at most 10%.

26. The molded object of any one of claims 22 to 25, wherein the haze measured according to ASTM D1003 for a sheet of 2mm thickness produced from the polyamide molding composition of any one of claims 1 to 19 is at most 3%.

27. A molded object as claimed in claim 22, produced from the molding composition as claimed in any of claims 1 to 19, characterized in that the deformation of the molded object is at most 4mm in a controlled-climate test, wherein the controlled-climate test measures the deformation of a sheet of dimensions 100 x 2mm, in which the deflection of the sheet under its own weight is determined at a temperature of 55 ℃ and a relative humidity of 95%, for which purpose one edge of the sheet is raised by 25mm and the deformation at the center of the sheet, i.e. the change in position relative to the initial conditions, is measured after 168 hours.

28. A molded object as claimed in claim 22, produced from the molding composition as claimed in any of claims 1 to 19, characterized in that the deformation of the molded object is at most 2mm in a controlled-climate-conditions test, wherein the controlled-climate-conditions test measures the deformation of a sheet of dimensions 100 x 2mm, in which the deflection of the sheet under its own weight is determined at a temperature of 55 ℃ and a relative humidity of 95%, for which purpose one edge of the sheet is raised by 25mm and the deformation at the center of the sheet, i.e. the change in position relative to the initial conditions, is measured after 168 hours.