KR102557042B1 - Glass fiber reinforced polyamide resin composition, method for preparing the same and molded product comprising the composition - Google Patents

Abstract

The present invention relates to a glass fiber-reinforced polyamide resin composition, a method for producing the same, and a molded product including the same, and more particularly, to a polyamide resin containing glass fibers of a specific composition, an olefin-based impact modifier, etc. in a specific content range. Provided are a fiber-reinforced polyamide resin composition, a method for preparing the same, and a molded article including the same.
The composition according to the present invention simultaneously satisfies high impact and high stiffness characteristics, has very excellent impact strength over a wide temperature range from low temperature (-40 ° C) to room temperature (23 ° C), and maintains the glass fiber content under equal conditions. It provides the advantage of maintaining a considerably high stiffness even when it is lowered, and the compatibility between the polyamide resin and the glass fiber is maximized, providing a very good overall balance of physical properties.

Description

Glass fiber-reinforced polyamide resin composition, manufacturing method thereof, and molded product including the same

The present invention relates to a glass fiber-reinforced polyamide resin composition, a manufacturing method thereof, and a molded product including the same, and more particularly, to a polyamide resin containing glass fibers of a specific composition, an olefin-based impact modifier, etc. It simultaneously satisfies both impact and high rigidity characteristics, while providing excellent impact strength over a wide temperature range from low temperature (-40℃) to room temperature (23℃), and it has the physical properties required when applied as an airbag mounting plate. It relates to a glass fiber-reinforced polyamide resin composition that can satisfy all of them, a manufacturing method thereof, and a molded article including the same.

Since the airbag module is a representative safety part of automobiles and is directly related to life, its operability and safety must be verified through real-vehicle deployment tests while satisfying all the various physical properties required.

The airbag module works in the following process: i) In the event of a collision, the impact detection sensor detects the amount of impact and recognizes an accident. ii) The inflator attached to the mounting plate explodes as heat is generated by electrically or mechanically igniting the igniter inside. iii) When the pressure increases due to the gas instantaneously generated by the explosion, the tear line of the airbag cover is opened and the airbag is deployed. The deployed airbag acts as a cushioning material to promote the safety of occupants.

As described above, as the airbag module is operated by the instantaneous explosion of the inflator, each component constituting the module requires high impact and high elongation characteristics so as not to generate cracks or fragments due to impact, and can withstand considerable energy from the explosion. High stiffness properties are also required.

In addition, since the airbag module can be placed in various temperature conditions, it must satisfy the above physical properties and deployment performance not only at room temperature (23°C) but also under extreme conditions (-35°C/+85°C). In particular, low-temperature and high-impact characteristics are required to prevent parts from being damaged or fragments generated due to an impact caused by an internal explosion under low-temperature conditions, and the airbag must be able to deploy without escaping in an unintended direction.

Meanwhile, parts of the airbag module to which plastic materials are applied can be largely divided into a cover and a mounting plate. The cover is mainly made of thermoplastic elastomer, and glass fiber reinforced polyamide resin is applied to the mounting plate. Since the mounting plate is a part to which the expander is directly coupled, it must be able to withstand high energy caused by the explosion of the expander, and therefore, high impact and high rigidity characteristics are further required. However, there is a problem in that simultaneous implementation is difficult due to a trade-off relationship between impact resistance and rigidity.

For example, when the content of glass fiber is increased, the stiffness of the material increases, but there is a problem that the impact strength and elongation decrease. To improve this, a technique for applying an impact modifier has been proposed, but glass fiber, polyamide and impact modifier It was difficult to improve the impact strength and stiffness at the same time due to low compatibility with each other.

Therefore, while realizing high impact and high elongation characteristics at the same time by maximizing the compatibility between each component, it has excellent impact properties in a wide range of temperatures from low temperature (-40 ℃) to room temperature (+23 ℃), and actual vehicle deployment performance ( It is required to develop a material for a mounting plate of an airbag module that satisfies operability and stability).

Korean Patent Publication No. 10-2010-0028161 A

In order to solve the problems of the prior art as described above, the present invention has excellent impact strength over a wide temperature range from low temperature (-40 ℃) to room temperature (23 ℃) while simultaneously satisfying high impact and high stiffness properties, An object of the present invention is to provide a glass fiber-reinforced polyamide resin composition having a very excellent balance of physical properties by maximizing the compatibility between a polyamide resin and glass fibers and a manufacturing method thereof.

Further, the present invention further aims to provide a molded article, particularly an automobile airbag mounting plate, comprising the composition.

The above and other objects can all be achieved by the present invention described below.

In order to achieve the above object, the present invention includes 40 to 62% by weight of a polyamide resin, 4 to 12% by weight of an olefin-based impact modifier, 0 to 5% by weight of a coupling agent, and 33 to 45% by weight of glass fiber, The glass fiber contains 58 to 66% by weight of silicon dioxide (SiO ₂ ), 14 to 25% by weight of aluminum oxide (Al ₂ O ₃ ), 0 to 13% by weight of calcium oxide (CaO), and magnesium oxide (based on the total amount of the glass fiber). It provides a glass fiber-reinforced polyamide resin composition characterized in that it consists of 0 to 12% by weight of MgO) and 0 to 10% by weight of other components.

In addition, the present invention includes the steps of kneading and extruding by including 40 to 62% by weight of a polyamide resin, 4 to 12% by weight of an olefinic impact modifier, 0 to 5% by weight of a coupling agent, and 33 to 45% by weight of glass fibers, , The glass fiber contains 58 to 66% by weight of silicon dioxide (SiO ₂ ), 14 to 25% by weight of aluminum oxide (Al ₂ O ₃ ), 0 to 13% by weight of calcium oxide (CaO), and oxide based on the total amount of the glass fiber. It provides a method for producing a glass fiber-reinforced polyamide resin composition, characterized in that it consists of 0 to 12% by weight of magnesium (MgO) and 0 to 10% by weight of other components.

In addition, the present invention provides a molded article comprising the glass fiber-reinforced polyamide resin composition.

The glass fiber-reinforced polyamide resin composition according to the present invention simultaneously satisfies high impact and high stiffness properties, and specifically, has excellent impact strength over a wide temperature range from low temperature (-40 ℃) to room temperature (23 ℃). And, it provides the advantage of maintaining a considerably high stiffness even when the content of glass fiber is lowered under the same conditions, and the compatibility between the polyamide resin and the glass fiber is maximized, providing a very good overall balance of physical properties.

Furthermore, the composition of the present invention can be used as a material for an airbag mounting plate of a vehicle, and exhibits high impact, high stiffness, and excellent elongation, thereby satisfying the physical properties required as a material for an airbag mounting plate, while demonstrating operability and stability during a real-vehicle deployment test. Satisfying all of them can contribute to improving the quality of airbags.

Hereinafter, the glass fiber-reinforced polyamide resin composition of the present disclosure will be described in detail.

In order to solve the above-mentioned problems of the prior art, the present inventors prepared a glass fiber-reinforced polyamide resin composition by blending a polyamide resin, an olefin-based impact modifier, glass fiber, etc. within a specific content range, but at this time, glass fibers of a specific composition For example, silicon dioxide (SiO ₂ ) 58 to 66% by weight, aluminum oxide (Al ₂ O ₃ ) 14 to 25% by weight, calcium oxide (CaO) 0 to 13% by weight, magnesium oxide (MgO) 0 to 12% by weight and other components, when using glass fibers composed of 0 to 10% by weight, the flexural modulus, low temperature (-40 ℃) and room temperature (23 ℃) impact strength, tensile strength and tensile elongation are all excellent, resulting in high impact, high stiffness and high It was confirmed that elongation characteristics could be provided at the same time, and based on this, further efforts were made to complete the present invention.

The glass fiber-reinforced polyamide resin composition of the present substrate includes, for example, 40 to 62% by weight of a polyamide resin, 4 to 12% by weight of an olefinic impact modifier, 0 to 5% by weight of a coupling agent, and 33 to 45% by weight of glass fiber, , The glass fiber contains 58 to 66% by weight of silicon dioxide (SiO ₂ ), 14 to 25% by weight of aluminum oxide (Al ₂ O ₃ ), 0 to 13% by weight of calcium oxide (CaO), and oxide based on the total amount of the glass fiber. It is characterized in that it consists of 0 to 12% by weight of magnesium (MgO) and 0 to 10% by weight of other components. It offers the advantage of very good impact strength within the temperature range. Due to this, the composition can be used as a mounting plate for an airbag, and can contribute to improving the quality of an airbag by satisfying both operability and stability during a real-vehicle deployment test while satisfying required mechanical properties.

Hereinafter, the glass fiber-reinforced polyamide resin composition of the present substrate will be described in detail for each component.

polyamide resin

The polyamide resin may be included in an amount of, for example, 40 to 62% by weight, 45 to 60% by weight, or 50 to 60% by weight, based on the total amount of the glass fiber-reinforced polyamide resin composition of the present disclosure, and within this range of the composition It has the advantage of being excellent in both rigidity and impact strength.

For example, the polyamide resin may be condensation-polymerized containing lactam or ω-amino acid alone or both thereof, or condensation-polymerized containing diamine and dibasic acid may be used.

For example, the polyamide resin may be a homopolyamide, a copolyamide, or a mixture thereof, and the polyamide resin may be semi-crystalline and/or amorphous.

As a specific example, the lactam may be at least one selected from caprolactam, laurolactam, enantlactam, piperidone, pyrrolidone, and the like, and the ω-amino acid is aminocaproic acid, 7-aminoheptanoic acid, 11-amino It may be at least one selected from undecanoic acid, 9-aminononanoic acid, 12-aminododecanoic acid, and para-aminomethylbenzoic acid.

The diamine may be, for example, at least one selected from aliphatic, alicyclic, or aromatic diamines, and specific examples include tetramethylenediamine, hexamethylenediamine, nonamethylenediamine, decamethylenediamine, undecamethylenediamine, dodecamethylenediamine, para Aminoaniline, metaxylenediamine, paraxylenediamine, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, 1-amino-3-aminomethyl-3,5,5- Trimethylcyclohexane, bis(4-aminocyclohexyl)methane, bis(3-methyl-4-aminocyclohexyl)methane, 2,2-bis(4-aminocyclohexyl)propane, bis(aminopropyl)piperazine, It may be at least one selected from aminoethylpiperazine and the like.

The dibasic acid may be, for example, at least one selected from aliphatic, alicyclic or aromatic dicarboxylic acids or acyl chlorides, and specific examples include adipic acid, sebacic acid, dodecanedioic acid, undecanedioic acid, heptanedioic acid, azela 1 selected from phosphoric acid, glutaric acid, terephthalic acid, methyl terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, adipoyl chloride, sebacoyl chloride, nonanedioyl chloride, dodecanedioyl dichloride, methyladipic acid, trimethyladipic acid, and the like There may be more than one species.

As a more specific example, the polyamide resin is a copolymer of nylon 6, nylon, 7, nylon 8, nylon 10, nylon 12, nylon 66, nylon 69, nylon 610, nylon 611, nylon 612, nylon 6T, nylon 6 and nylon 66. It may include at least one selected from a copolymer, a copolymer of nylon 6 and nylon 12, and a copolymer of nylon 6 and nylon 6T, preferably selected from nylon 6, nylon 66, or copolymers thereof. In this case, there is an advantage in that the overall physical property balance of the composition is excellent.

As a more preferable example, the polyamide resin may be nylon 6 (polycaprolactam), and in this case, the composition is easy to mold and has superior impact resistance.

The polyamide resin may have, for example, a relative viscosity of 2.0 to 3.0 cP, preferably 2.2 to 2.8 cP, and within this range, the composition has an excellent physical property balance and is easy to mold.

In this description, the relative viscosity is a value measured at 25° C. after preparing by dissolving 1 g of resin in 100 ml of a sulfuric acid solution having a concentration of 96% by weight, unless otherwise specified.

As a preferred example, the polyamide resin may be nylon 6 having a relative viscosity of 2.2 to 2.8 cP, and in this case, a better balance of physical properties is provided.

olefinic impact modifier

The olefin-based impact modifier may be included in an amount of, for example, 4 to 12% by weight, 5 to 10% by weight, or 7 to 10% by weight based on the total amount of the glass fiber-reinforced polyamide resin composition of the present substrate, within this range It provides the advantage of improving the impact properties while maintaining the high, and has the advantage of easy molding.

The olefin-based impact modifier means a homopolymer of an olefin-based compound, a copolymer containing an olefin-based compound, or a mixture thereof.

The olefin-based compound may be, for example, at least one selected from ethylene and an alpha olefin having 3 to 20 carbon atoms.

The alpha olefin having 3 to 20 carbon atoms is, for example, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, 1-undecene, It may be one or more selected from 1-dodecene, 1-tetradecene, 1-hexadecene, 1-eicosene, styrene, alpha-methylstyrene, divinylbenzene, etc., preferably propylene, 1-butene and 1- It may be one or more selected from octene.

In another example, the olefin-based impact modifier may be a copolymer of an olefin-based compound and a compound copolymerizable therewith.

The copolymerizable compound may be, for example, at least one selected from diene monomers and vinyl acetate, and the diene monomers may be, for example, 1,4-butadiene, 1,5-butadiene, 1,5-pentadiene, and 1,6-hexadiene. , norbornene, ethylidenenorbornene, phenyl norbornene, and dicyclopentadiene.

In a preferred embodiment, the olefinic impact modifier is one selected from polyethylene, polypropylene, ethylene-C3-C20 alpha olefin copolymer, ethylene-vinyl acetate copolymer, ethylene-C3-C20 alpha olefin-diene monomer copolymer There may be more than one species.

As a more specific example, the olefinic impact modifier may use at least one selected from polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-octene copolymer, ethylene-butene copolymer, and ethylene-propylene diene monomer copolymer, The most preferred example is an ethylene-propylene copolymer, and in this case, all physical properties such as impact strength, stiffness, and elongation of the composition can be maintained high.

The olefin-based impact modifier may be, for example, a modified polyolefin grafted with at least one selected from an unsaturated carboxylic acid, an anhydride thereof, and a glycidyl-based compound on an olefin-based polymer. In this case, compatibility between polyamide, glass fiber, and the impact modifier The property is improved and the physical property balance provides a better advantage.

The unsaturated carboxylic acid may be, for example, at least one selected from maleic acid, fumaric acid, itaconic acid, citraconic acid, mesaconic acid, and phthalic acid, and preferably maleic acid.

The glycidyl-based compound may be, for example, at least one selected from glycidyl methacrylate and glycidyl acrylate.

The modified polyolefin may include, for example, 0.1 to 5% by weight or 0.5 to 2% by weight of at least one selected from among unsaturated carboxylic acids, anhydrides thereof, and glycidyl-based compounds based on the total weight of the polyolefin. In this case, the impact While the strength is improved, the compatibility between each component in the composition is improved, providing an excellent advantage in overall physical property balance.

The olefin-based impact modifier is preferably a modified polyolefin grafted with maleic acid or its anhydride from the viewpoint of maximizing the compatibility between polyamide, glass fiber, and olefin-based impact modifier, and more preferably maleic acid anhydride-modified ethylene -It may be a propylene copolymer.

fiberglass

The glass fibers may be included in an amount of, for example, 33 to 45% by weight, 35 to 45% by weight, or 38 to 44% by weight based on the total amount of the glass fiber-reinforced polyamide resin composition of the present substrate, and within this range, high impact and High rigidity can be secured at the same time.

Unless otherwise specified in this description, the content of each component constituting the glass fiber is expressed as a percentage by weight of each component based on the total amount of glass fiber.

The glass fiber is, for example, silicon dioxide (SiO ₂ ) 58 to 66% by weight, aluminum oxide (Al ₂ O ₃ ) 14 to 25% by weight, calcium oxide (CaO) 0 to 13% by weight, magnesium oxide (MgO) 0 to 25% by weight 12% by weight and 0 to 10% by weight of other components may be used. In this case, the composition has excellent impact strength and rigidity, especially in a wide temperature range from low temperature to room temperature (-40 ℃ to 23 ℃). can be greatly improved.

As a specific example, the glass fiber having the above composition may be at least one of S-glass, R-glass and Te-glass described in "ASM Handbook, Vol. 21: Composites (# 06781G)".

The glass fiber exhibits, for example, 10% or more higher tensile strength than E-glass specified in ASTM D578.

The glass fiber is another example of silicon dioxide (SiO ₂ ) 58 to 66% by weight, aluminum oxide (Al ₂ O ₃ ) 14 to 21% by weight, calcium oxide (CaO) 0.5 to 13% by weight, magnesium oxide (MgO) 8 to 12% by weight and 0 to 10% by weight of other components may be used. In this case, the composition has excellent impact strength and stiffness, especially in a wide temperature range from low temperature to room temperature (-40 ℃ to 23 ℃) Strength provides superior advantages.

The glass fiber is another example of silicon dioxide (SiO ₂ ) 58 to 62% by weight, aluminum oxide (Al ₂ O ₃ ) 14 to 18% by weight, calcium oxide (CaO) 10 to 13% by weight, magnesium oxide (MgO) 8 to 10% by weight and 0.1 to 5% by weight of other components may be used. In this case, the impact strength and stiffness of the composition are greatly improved at the same time, contributing to product quality improvement and providing advantageous advantages in terms of unit cost reduction. do.

Unless otherwise specified in this description, the content of each component constituting the other components is expressed as a percentage based on the total amount of glass fibers.

The other components are, for example, sodium oxide (Na ₂ O), potassium oxide (K ₂ O), iron oxide (Fe ₂ O ₃ ), titanium dioxide (TiO ₂ ), lithium oxide (LiO ₂ ) and zirconium oxide (Zr ₂ O ). ₃ ) may include one or more selected from, which may be included in an amount of 0 to 10% by weight or more than 0% by weight to 10% by weight or less, for example.

As a specific example, the total amount of sodium oxide (Na ₂ O) and potassium oxide (K ₂ O) may be 0 to 1 wt%, 0.8 wt% or less, more than 0 wt% to 0.8 wt% or less, or 0.1 to 0.8 wt%. there is.

As a specific example, the iron oxide (Fe ₂ O ₃ ) may be included in an amount of 0 to 1 wt%, more than 0 wt% to less than 0.7 wt%, or more than 0 wt% to less than 0.5 wt%.

As a specific example, the titanium dioxide (TiO ₂ ) may be included in an amount greater than 0% by weight and less than or equal to 3% by weight, 0.4 to 3% by weight, or 0.5 to 2% by weight.

As a specific example, the lithium oxide (LiO ₂ ) may be included in an amount of 0 to 2% by weight or 0.5 to 2% by weight.

As a specific example, the zirconium oxide (Zr ₂ O ₃ ) may be included in an amount of 0 to 1.5% by weight or 0 to 1% by weight.

Each of the glass fibers exemplified above may be boron oxide (B ₂ O ₃ )-free glass fibers that do not contain boron oxide (B ₂ O ₃ ), and in this case, the tensile properties of the composition, impact strength, etc. It provides the advantage of improved physical properties and excellent balance of physical properties.

The glass fiber may have a softening point of, for example, 905 to 920 °C or 910 to 920 °C, and in this case, the balance of physical properties of the composition is excellent.

In this description, the softening point of glass fiber represents a value measured according to the method specified in ASTM C338, for example, unless otherwise specified.

The glass fiber may have a tensile strength of, for example, 2500 to 3000 MPa or 2500 to 2900 MPa, and in this case, the tensile properties are improved while maintaining high impact strength of the composition.

The glass fiber may be characterized by a tensile modulus of, for example, 88 to 95 GPa or 88 to 92 GPa, and within this range, the composition has an excellent balance of toughness and stiffness.

In this description, the tensile strength and tensile modulus of glass fiber represent values measured according to the method specified in ASTM D2343, for example, unless otherwise specified.

The glass fiber may be characterized in that, for example, the length is 1 to 10 mm or 1 to 5 mm and the diameter is 5 to 20 μm or 10 to 15 μm. There is an advantage that the appearance of the molded article is excellent.

In this description, unless otherwise specified, the length and diameter of glass fibers were measured by using an optical microscope for 40 lengths and diameters, and the average value was calculated.

The glass fiber may be surface-treated to increase interfacial bonding strength, and for example, one selected from amino silane, epoxy silane, amide silane, azide silane, acryl silane, monoalkoxy titanate, zirconate-based binder, etc. What has been surface-treated with the above compound can be used.

coupling agent

The composition of the present substrate may further include a coupling agent for the purpose of further maximizing the compatibility between polyamide and glass fibers to improve the flexural modulus and tensile strength of the composition, and the coupling agent is the glass fiber-reinforced poly of the present substrate It may be included in a ratio of, for example, 0 to 5% by weight, 0.2 to 3% by weight, or 0.5 to 1% by weight based on the total amount of the amide resin composition.

The coupling agent may be, for example, a silane-based coupling agent, and in this case, it is possible to maintain a high overall physical property balance by maximizing compatibility without affecting the physical properties of the composition.

The silane-based coupling agent may be, for example, an amino silane-based compound, an epoxy silane-based compound, or both, and preferably an amino silane-based compound.

As a specific example, the amino silane-based compound is (3-aminopropyl)trimethoxysilane, (3-aminopropyl)triethoxysilane, bis(2-hydroxyethyl)-3-aminopropyl trialkoxysilane, diethyl Aminomethyltrialkoxysilane, (N,N-diethyl-3-aminopropyl) trialkoxysilane, (2-N-benzylaminoethyl)-3-aminopropyl trialkoxysilane, bis(methyldialkoxysilylpropyl)- 1 selected from N-methylamine, bis(trialkoxysilylpropyl) urea, bis(3-(trialkoxysilyl)propyl)-ethylenediamine, bis(trialkoxysilylpropyl)amine and bis(trimethoxysilylpropyl)amine It may be more than one species, preferably (3-aminopropyl)triethoxysilane.

The composition of the present substrate may be characterized in that the polyamide resin and the glass fiber are included in a weight ratio of, for example, 1:0.5 to 1:1, 1:0.6 to 1:1, or 1:0.7 to 1:1, , within this range, there is an advantage in that the balance of physical properties such as flexural modulus, impact strength, and tensile properties are excellent.

Other Additives

The composition of the present substrate optionally contains at least one additive selected from a stabilizer, a lubricant, a release agent, a pigment, a dye, a flame retardant, a reinforcing agent, an antioxidant, an antistatic agent, a conductive additive, an EMI shielding agent, a nucleating agent, an antibacterial agent, and a deodorant, as needed. can include more.

The composition provides the advantage of excellent low-temperature impact resistance, with a low-temperature (-40 ° C) Izod impact strength of, for example, 15.0 kg.cm / cm or more, 15 to 20 kg.cm / cm, or 16 to 18 kg.cm / cm. .

For example, the composition has an Izod impact strength of 20 to 30 kg.cm/cm or 23 to 28 kg.cm/cm at room temperature (23° C.), providing excellent room temperature impact resistance.

Unless otherwise specified in this description, room temperature and low temperature Izod impact strength is a value measured according to the method specified in ASTM D256, and specifically, a specimen with a thickness of 6.4 mm and a width of 12.7 mm is prepared, and 40 ° C) or room temperature (23 ° C) after aging for 4 hours.

The composition has a flexural modulus of, for example, 93000 kg/cm ² , 93000 to 120000 kg/cm ² , or 100000 to 120000 kg/cm ² , providing an advantage of excellent rigidity.

Unless otherwise specified in this description, the flexural modulus is a value measured according to the method specified in ASTM D790, and specifically, a specimen having a thickness of 6.4 mm and a width of 12.7 mm was prepared and measured under the condition of a measurement speed of 3 mm/min.

The composition provides excellent advantages with a tensile elongation of, for example, 4.0 to 6.0% or 5.0 to 6.0%.

The composition provides an excellent advantage in tensile strength of, for example, 1500 kg/cm ² or more or 1500 to 1900 kg/cm ² .

Unless otherwise specified in this description, tensile elongation and tensile strength are values measured for elongation and strength at break according to the method specified in ASTM D638. Specifically, after preparing a specimen with a thickness of 3.2 mm and a width of 12.7 mm, The measurement was performed under the conditions of a gauge line distance of 50 mm and a measurement speed of 5 mm/min.

Hereinafter, a method for manufacturing the glass fiber-reinforced polyamide resin composition of the present disclosure will be described. The manufacturing method is a manufacturing method of the above-described glass fiber-reinforced polyamide resin composition, and descriptions overlapping with the above will be omitted.

The method for producing the glass fiber-reinforced polyamide resin composition of the present substrate includes, for example, 40 to 62% by weight of a polyamide resin, 4 to 12% by weight of an olefinic impact modifier, 0 to 5% by weight of a coupling agent, and 33 to 45% by weight of glass fiber. Including the steps of kneading and extruding, but the glass fibers are based on the total amount of the glass fibers, silicon dioxide (SiO ₂ ) 58 to 66% by weight, aluminum oxide (Al ₂ O ₃ ) 14 to 25% by weight, oxide It is characterized in that it consists of 0 to 13% by weight of calcium (CaO), 0 to 12% by weight of magnesium oxide (MgO), and 0 to 10% by weight of other components, and the composition prepared in this way simultaneously secures high impact and high stiffness properties. It is possible, has excellent elongation, and provides very good impact strength within a wide temperature range from low temperature to room temperature. Furthermore, the prepared composition can be used as a mounting plate for an airbag, and can contribute to improving the quality of an airbag by satisfying both operability and stability during a real-vehicle deployment test while satisfying required mechanical properties.

The kneading and extrusion may be performed under temperature conditions of 200 to 300 ° C. or 250 to 290 ° C. using an extrusion processing device such as a twin screw extruder or a single screw extruder after primary mixing in a Banbari mixer or a super mixer, for example. It is not necessarily limited to this.

In addition, during the kneading, the above-mentioned additives may be further added selectively as needed.

The glass fiber-reinforced polyamide resin composition of the present disclosure may be provided as a molded article through various molding processes.

The molded article of the present substrate, including the glass fiber-reinforced polyamide resin composition, simultaneously satisfies high impact and high stiffness properties, has excellent elongation, and provides very good impact strength within a wide temperature range from low temperature to room temperature. do.

Furthermore, the molded article can be used as a mounting plate for an airbag, and can contribute to improving the quality of an airbag by satisfying both operability and stability during a real-vehicle deployment test while satisfying required mechanical properties.

In describing the glass fiber-reinforced polyamide resin composition of the present description, its manufacturing method and molded article, other additives, conditions, equipment, etc. not explicitly described can be appropriately selected within the range commonly practiced in the art, , it is stated that it is not particularly limited.

Hereinafter, preferred embodiments are presented to aid understanding of the present invention, but the following examples are merely illustrative of the present invention, and various changes and modifications are possible within the scope and spirit of the present invention. It is obvious to those skilled in the art, It goes without saying that these variations and modifications fall within the scope of the appended claims.

Materials used in the following Examples and Comparative Examples are as follows.

*Polyamide resin

Nylon 6 (polycaprolactam) with a relative viscosity of 2.5 cP was used.

*Olefin system impact modifier

An ethylene-propylene copolymer grafted with maleic anhydride was used.

*Glass fiber 1

Glass fibers having the following composition and physical properties were used. (Diameter: 11㎛, Length: 3mm)

- Silicon dioxide (SiO ₂ ) 58 ~ 62% by weight

- 14 to 18% by weight of aluminum oxide (Al ₂ O ₃ )

- Calcium oxide (CaO) 10-13% by weight

- Magnesium oxide (MgO) 8-10% by weight

-Other components: Na ₂ O + K ₂ O ≤ 0.8% by weight, Fe ₂ O ₃ ≤ 0.5% by weight, TiO ₂ 0.5-2.0% by weight included

- Softening point: 910~920℃

- Tensile strength: 2500~2900MPa

- Tensile modulus: 88~92GPa

*Glass fiber 2

Glass fibers having the following composition were used.

- Silicon dioxide (SiO ₂ ) 57-61% by weight

- 11 to 15% by weight of aluminum oxide (Al ₂ O ₃ )

- 20 to 24% by weight of calcium oxide (CaO)

- 2 to 5% by weight of magnesium oxide (MgO)

- Other components: Na ₂ O + K ₂ O ≤ 0.8 wt%, Fe ₂ O ₃ ≤ 0.5 wt%, TiO ₂ ≤ 0.5 wt%

* coupling agent

Momentive's Silquest A-1100 product (3-aminopropyl triethoxysilane) was used.

[Examples and Comparative Examples]

Example 1 to 3 and comparative example 1 to 5

The components and contents shown in Table 1 below were mixed, and kneaded and extruded (temperature: 260° C., 250 rpm) to prepare a glass fiber-reinforced polyamide resin composition. This was manufactured into pellets using a pelletizer and injected to prepare a specimen for measuring physical properties.

[Test Example]

The physical properties of the specimens prepared in the above Examples and Comparative Examples were measured by the following method, and the results are shown in Table 1 below.

*curve modulus of elasticity (Unit: kg/ cm ² )

After preparing a specimen having a thickness of 6.4 mm and a width of 12.7 mm according to the method specified in ASTM D790, it was measured under the condition of a measurement speed of 3 mm/min.

* Izod Impact strength (unit: kg cm/cm)

After preparing a specimen with a thickness of 6.4 mm and a width of 12.7 mm according to the method specified in ASTM D256, the low-temperature and room-temperature impact strengths were measured using a low-temperature impact tester from Toyoseiki. Specifically, the low-temperature impact strength was measured after aging the specimen for 4 hours under the condition that the chamber temperature was low (-40 ℃), and the room temperature impact strength was measured after aging for 4 hours under the condition that the chamber temperature was room temperature (23 ℃). measured.

*Tensile strength (Unit: kg/ cm ² ) and tensile elongation (unit: % )

Tensile strength and tensile elongation at break were measured according to the method specified in ASTM D638. Specifically, after manufacturing a specimen with a thickness of 3.2mm and a width of 12.7mm, the measurement was performed under the conditions of a gauge distance of 50mm and a measurement speed of 5mm/min. did

division Example comparative example One 2 3 One 2 3 4 5 Polyamide resin [% by weight] 59 52.5 46 52 52.8 36 63.5 46 Olefin-based impact modifier [wt%] 5 7 10 6 8 9 5 13 Glass fiber 1 [% by weight] 36 40 44 - - - 30 - Glass fiber 2 [% by weight] - - - 42 39 50 - 41 coupling agent - 0.5 - - 0.2 5 1.5 - Flexural modulus (unit: kg/cm ² ) 93500 105000 100000 85700 84000 95000 83500 77000 Room temperature Izod impact strength (unit: kg cm/cm) 23.3 26.0 24.9 19.7 21.4 17.8 20.7 23.6 Low temperature Izod impact strength (unit: kg cm/cm) 15.1 16.5 16.0 13.3 13.9 9.5 12.8 14.8 Tensile strength (unit: kg/cm ² ) 1520 1750 1670 1480 1380 1530 1410 1290 Tensile Elongation (Unit: %) 4.3 5.5 4.6 2.3 2.8 3.2 3.9 3.3

(In Table 1, the content of each component is based on the total amount of polyamide resin, olefin-based impact modifier, and glass fiber.)

Referring to Table 1, in the case of Examples 1 to 3 using the glass fibers of the composition according to the present invention, compared to Comparative Examples 1 to 3 and 5 using the glass fibers of a different composition from the present application, the flexural modulus, room temperature and low temperature Izod impact It can be seen that the strength, tensile strength and tensile elongation are generally excellent, and the balance of physical properties is excellent.

In particular, in the case of Examples 1 to 3, the low-temperature Izod impact strength was absolutely superior to that of the comparative example, and in the case of Example 2 including the coupling agent, the flexural modulus, room temperature and low-temperature Izod impact strength, tensile strength and tensile elongation were more It was confirmed that the balance of physical properties was excellent.

For reference, glass fiber 2 used in Comparative Examples 1 to 3 and 5 is an example of E-glass-based glass fiber specified in ASTM D578, and the content of calcium oxide (CaO) is 20% by weight or more, which is an excess of the present invention. It is distinct from the glass fibers of

In addition, from Example 1 of the present application, when the content of the impact modifier is less than 4% by weight, even if the glass fiber corresponding to the present invention is prescribed, it is predicted that the low-temperature impact strength improvement effect will be insufficient, and a separate test for this was not conducted.

On the other hand, in the case of Comparative Example 4 in which the weight ratio of the polyamide resin and the glass fiber is less than 1:0.5 even though the glass fibers of the composition according to the present invention are included, even though the impact modifier and the coupling agent are prescribed in appropriate amounts, the flexural modulus compared to the example , It was confirmed that the tensile strength and tensile elongation were lowered, and the low temperature impact strength was not improved.

In addition, referring to Comparative Example 5, it was confirmed that the room temperature impact strength was good due to the excessive prescription of the impact modifier, but the flexural modulus, tensile strength and tensile elongation were significantly lower than those of the examples, and the effect of improving the low temperature impact strength was insufficient.

That is, conventionally, the room temperature impact strength can be improved to some extent by prescribing an excessive amount of the impact modifier, but the physical property balance becomes very poor as the content thereof increases, and the effect of improving the impact strength over a wide temperature range from low temperature to room temperature is could not be achieved However, it was confirmed that when the glass fiber having the same composition as the present invention is formulated, even when a small amount of an impact modifier is added, the impact strength at both room temperature and low temperature is greatly improved, thereby achieving an effect that could not be achieved in the past.

From this, it can be predicted that the glass fiber-reinforced polyamide resin composition according to the present invention and the molded article manufactured therefrom can be used for an airbag mounting plate of a vehicle and contribute to improving the performance and quality of an airbag.

Claims (18)

As a nanoclay-free polyamide resin composition,
40 to 62% by weight of polyamide resin, 4 to 12% by weight of olefinic impact modifier, 0 to 5% by weight of coupling agent, and 33 to 45% by weight of glass fiber,
The polyamide resin and the glass fiber are included in a weight ratio of 1:0.7 to 1:1,
Aluminum oxide constituting the glass fiber is included in excess of calcium oxide,
The glass fiber contains 58 to 66% by weight of silicon dioxide (SiO ₂ ), 14 to 21% by weight of aluminum oxide (Al ₂ O ₃ ), 0.5 to 13% by weight of calcium oxide (CaO), and 8 to 12% by weight of magnesium oxide (MgO). % and other components from 0 to 10% by weight,
Characterized in that the low temperature (-40 ℃) Izod impact strength is 15.0 kg.cm / cm or more
A glass fiber reinforced polyamide resin composition. According to claim 1,
The polyamide resin is characterized in that the relative viscosity of 2.0 to 3.0cP
A glass fiber reinforced polyamide resin composition. According to claim 1,
Characterized in that the olefinic impact modifier comprises at least one selected from polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-octene copolymer, ethylene-butene copolymer and ethylene-propylene diene monomer copolymer
A glass fiber reinforced polyamide resin composition. According to claim 1,
Characterized in that the olefin-based impact modifier is a modified polyolefin grafted with at least one selected from an unsaturated carboxylic acid, an anhydride thereof, and a glycidyl-based compound on an olefin-based polymer.
A glass fiber reinforced polyamide resin composition. According to claim 1,
Characterized in that the coupling agent comprises a silane-based coupling agent
A glass fiber reinforced polyamide resin composition. According to claim 1,
The glass fiber is characterized in that the softening point (softening point) is 905 to 920 ℃
A glass fiber reinforced polyamide resin composition. According to claim 1,
The glass fiber is characterized in that the tensile strength of 2500 to 3000MPa
A glass fiber reinforced polyamide resin composition. According to claim 1,
Characterized in that the glass fiber has a tensile modulus of 88 to 92 GPa
A glass fiber reinforced polyamide resin composition. delete According to claim 1,
The glass fiber contains 58 to 62% by weight of silicon dioxide (SiO ₂ ), 14 to 18% by weight of aluminum oxide (Al ₂ O ₃ ), 10 to 13% by weight of calcium oxide (CaO), and 8 to 10% by weight of magnesium oxide (MgO). % and other components from 0.1 to 5% by weight, characterized in that
A glass fiber reinforced polyamide resin composition. According to claim 1,
The other ingredients are sodium oxide (Na ₂ O), potassium oxide (K ₂ O), iron oxide (Fe ₂ O ₃ ), titanium dioxide (TiO ₂ ), lithium oxide (LiO ₂ ) and zirconium oxide (Zr ₂ O ₃ ). Characterized in that it comprises at least one selected from
A glass fiber reinforced polyamide resin composition. According to claim 1,
Characterized in that the glass fiber is a boron oxide (B ₂ O ₃ )-free glass fiber.
A glass fiber reinforced polyamide resin composition. delete According to claim 1,
The composition is characterized in that the tensile elongation is 4.0% to 6.0%
A glass fiber reinforced polyamide resin composition. delete 40 to 62% by weight of a polyamide resin, 4 to 12% by weight of an olefin-based impact modifier, 0 to 5% by weight of a coupling agent, and 33 to 45% by weight of glass fibers, including kneading and extruding,
The polyamide resin and the glass fiber are included in a weight ratio of 1:0.7 to 1:1,
Aluminum oxide constituting the glass fiber is included in excess of calcium oxide,
The glass fibers are 58 to 66% by weight of silicon dioxide (SiO ₂ ), 14 to 25% by weight of aluminum oxide (Al ₂ O ₃ ), 0 to 13% by weight of calcium oxide (CaO), and magnesium oxide based on the total amount of the glass fibers. (MgO) 0 to 12% by weight and other components 0 to 10% by weight,
Characterized in that the low temperature (-40 ℃) Izod impact strength is 15.0 kg.cm / cm or more
A method for producing a glass fiber reinforced polyamide resin composition. It is characterized in that it comprises the glass fiber-reinforced polyamide resin composition according to any one of claims 1 to 8
molding. According to claim 17,
The molded article is characterized in that the airbag mounting plate of the vehicle
molding.