【発明の詳細な説明】[Detailed description of the invention]
本発明は、強化ポリアミド樹脂組成物に関す
る。さらに詳しくは、優れた諸特性を損うことな
く、改良された落錘衝撃強度を有する成形品を与
えることのできる強化ポリアミド樹脂組成物に関
する。
ナイロン66に無機鉱物粉末を配合した強化ナイ
ロン66は強靱性、耐熱性、寸法安定性に優れ、さ
らには油類をはじめ多くの薬品に対して耐久性を
有している為、自動車、電気、機械などの部品と
して多く使用されている。しかしながら、特定の
用途においては、従来の強化ナイロン66では落錘
衝撃強度が不充分であり、特に自動車の部品分野
や機械のハウジング分野での使用に大きな制約が
あつた。
従来、この種の問題を解決する方法として、例
えば特公昭54−4743号公報に見られるがごとく、
強化ポリアミドにエチレン系アイオノマーを配合
して耐衝撃性を改良する方法が採用されている。
しかしながらこのような方法では強化ナイロン66
の優れた特性である耐熱性や強靱性を損つてしま
い、厳しい特性を要求される用途には不充分であ
つた。
本発明者等は強化ナイロン66の優れた諸特性を
損うことなく、落錘衝撃強度の改善された強化ポ
リアミド樹脂、即ち、前記自動車の部品分野や機
械のハウジング分野での使用に耐え得るポリアミ
ド樹脂組成物について、鋭意検討した結果、驚く
べきことに、ナイロン66樹脂に第２の構成樹脂と
してナイロン６樹脂を配合した場合、上記問題が
解消されること、更にこのナイロン６樹脂の配合
効果がビニルトリエトキシシランで表面処理され
た焼成カオリン粉末で強化した組成物において殊
に大きいことを見い出し、本発明に至つたもので
ある。
すなわち、本発明はナイロン66樹脂85〜99重量
％とナイロン６樹脂15〜１重量％とからなる樹脂
混合物100重量部と、ビニルトリエトキシシラン
で表面処理された焼成カオリン粉末10〜100重量
部とからなる強化ポリアミド樹脂組成物に関する
ものであり、該樹脂組成物は自動車部品材料とし
て好適である。
以下本発明組成物を説明する。
本発明に用いるナイロン66樹脂は、ヘキサメチ
レンアジパミド単位90モル％以上を有するポリア
ミド類であつて、他のコモノマー成分として、例
えばε−カプロラクタム、ω−ラウロラクタム、
ヘキサメチレンジアミンとセバシン酸の塩、ヘキ
サメチレンジアミンとドデカン二酸の塩などを10
モル％未満含有するものであつてもよい。またこ
れらのコモノマーは１種又は２種以上を組み合わ
せて含有させることができる。ナイロン66樹脂の
分子量については特に限定されないが、通常射出
成形などによる成形物の製造に使用される分子量
範囲のものを包含する。
本発明に使用される第２の構成樹脂であるナイ
ロン６樹脂はカプロラクタム単位を90モル％以上
有するポリアミド類であつて、他のコモノマー成
分として、ω−ラウロラクタム、ヘキサメチレン
ジアミンとアジピン酸の塩、ヘキサメチレンジア
ミンとドデカン二酸の塩などの１種又は２種以上
を10モル％未満含有してもよい。このナイロン６
樹脂の分子量も特に限定されず、通常の成形条件
で成形可能な分子量範囲にあるものが好ましい。
本発明において、ナイロン66樹脂とナイロン６
樹脂との混合割合はナイロン66樹脂85〜99重量
％、ナイロン６樹脂15〜１重量％である。ナイロ
ン66樹脂の混合割合が85重量％よりも少ないと耐
熱性や剛性が低下し、また99重量％よりも多い
と、落錘衝撃強度の改善効果がほとんどない。そ
の配合割合は特に90〜97重量％が好ましい。
本発明に述べる焼成カオリン粉末は、カオリン
粘度を350〜1000℃の温度範囲で数時間焼成後粉
砕されたものであり、平均粒子サイズが10μ以
下、特に2μ以下のものが好ましい。この焼成カ
オリンをビニルトリエトキシシランを用いて表面
処理したものが本発明に用いられる。
本発明において使用されるビニルトリエトキシ
シランで表面処理された焼成カオリン粉末の配合
量はナイロン66樹脂とナイロン６樹脂とからなる
樹脂混合物100重量部に対して10〜100重量部であ
り、10重量部未満では補強効果が不足するので好
ましくなく、100重量部を超えると成形時の流動
性が低下するため、成形工程における作業性が困
難となる。また使用する機械類の損耗の度合が大
きくなり、さらに均一な混合分散状態が得難くな
つて成形品の表面状態が悪くなるので好ましくな
い。
本発明の強化ポリアミド樹脂組成物の調製は、
通常のポリアミド組成物の調製方法によつて行わ
れる。例えばナイロン66樹脂、ナイロン６樹脂及
びビニルトリエトキシシランで表面処理された焼
成カオリン粉末とを予備混合し、これを押出機に
供給し溶融混練した後、冷却しペレツト化する方
法、あるいはあらかじめ調製したおいた無機鉱物
粉末含有強化ナイロン66樹脂にナイロン６樹脂を
ドライブレンドして成形する方法等が挙げられ
る。
本発明の強化ポリアミド樹脂組成物には、その
成形性、物性を損わない限りに於て他の成分、例
えば顔料、染料、耐熱剤、酸化劣化防止剤、滑
剤、難撚剤、帯電防止剤、離型剤、可塑剤、他の
樹脂ポリマー、繊維状補強材等を添加することが
できる。
以下、実施例により本発明を更に詳しく説明す
る。
なお、実施例および比較例に記した試験片の物
性測定は次の方法に従つて行つた。
(1) 引張試験 ：ASTM D638
(2) 曲げ試験 ：ASTM D790
(3) 熱変形温度 ：ASTM D648
(4) 落錘衝撃強度：JIS K7211
実施例 １
相対粘度2.80のナイロン66；95重量部と相対粘
度2.75のナイロン６；５重量部とビニルトリエト
キシシラン（信越シリコン製KBE1003）で表面
処理された焼成カオリン（ENGEL HARD社
製：
Satintone No.１）；67重量部とをＶ型ブレ
ンダーで予備混合し、ついで70mmφ単軸押出機を
用いて、290℃で溶融混合し、冷却してペレツト
を得た。得られたペレツトを射出成形機を用いて
290℃の温度で物性測定用試験片に成形し、諸物
性を評価した。その結果を第１表に示す。
実施例 ２
ナイロン66；90重量部、ナイロン６；10重量部
とした以外は実施例１と全く同様にして物性測定
用試験片を成形し、諸物性を評価した。その結果
を第１表に示す。
実施例 ３
ナイロン66；98重量部、ナイロン６；２重量部
とした以外は実施例１と全く同様にして物性測定
用試験片を成形し、諸物性を評価した。その結果
を第１表に示す。
実施例 ４
ナイロン66：87重量部、ナイロン６；13重量部
とした以外は実施例１と全く同様にして物性測定
用試験片を成形し、諸物性を評価した。その結果
を第１表に示す。
比較例 １
ナイロン66；80重量部、ナイロン６；20重量部
とした以外は実施例１と全く同様にして物性測定
用試験片を成形し、諸物性を評価した。その結果
を第１表に示す。
比較例 ２
ナイロン66を100重量部とし、ナイロン６を用
いない以外は実施例１と全く同様にして物性測定
用試験片を成形し、諸物性を評価した。その結果
を第１表に示す。
比較例 ３
焼成カオリンを150重量部とした以外は実施例
１と全く同様にして物性測定用試験片を成形し、
諸物性を評価した。その結果を第１表に示す。
比較例 ４
焼成カオリンを5.3重量部とした以外は実施例
１と全く同様にして物性測定用試験片を成形し、
諸物性を評価した。その結果を第１表に示す。
比較例 ５
焼成カオリンの代りにカオリン（ENGEL
HARD製ASP200）を用いた以外は実施例１と全
く同様にして物性測定用試験片を成形し、諸物性
を評価した。その結果を第１表に示す。
比較例 ６
相対粘度2.80のナイロン66；95重量部、相対粘
度2.75のナイロン６；５重量部、ガラス繊維（旭
フアイバーグラス製MA416）50重量部とした以
外は実施例１と全く同様にして物性測定用試験片
を成形し、諸物性を評価した。その結果を第１表
に示す。
比較例 ７
ナイロン66を100重量部としナイロン６を用い
なかつた以外は比較例６と全く同様にして物性測
定用試験片を成形し、諸物性を評価した。その結
果を第１表に示す。
The present invention relates to reinforced polyamide resin compositions. More specifically, the present invention relates to a reinforced polyamide resin composition that can provide a molded article with improved falling weight impact strength without sacrificing its excellent properties. Reinforced nylon 66, which is a mixture of nylon 66 and inorganic mineral powder, has excellent toughness, heat resistance, and dimensional stability, and is also resistant to oils and many chemicals, so it is used in automobiles, electrical appliances, It is often used as a part for machinery, etc. However, in certain applications, conventional reinforced nylon 66 has insufficient falling weight impact strength, which has placed significant restrictions on its use, particularly in the fields of automobile parts and machine housings. Conventionally, as a method to solve this kind of problem, as seen in Japanese Patent Publication No. 54-4743,
A method has been adopted in which impact resistance is improved by blending an ethylene ionomer with reinforced polyamide.
However, in this method, reinforced nylon 66
This impairs the excellent properties of heat resistance and toughness, making it unsatisfactory for applications requiring strict properties. The present inventors have developed a reinforced polyamide resin that has improved drop weight impact strength without sacrificing the excellent properties of reinforced nylon 66, that is, a polyamide resin that can withstand use in the automotive parts field and machine housing field. As a result of extensive research into resin compositions, we surprisingly found that when nylon 6 resin is blended with nylon 6 resin as a second component resin, the above problem is resolved, and furthermore, the effect of blending this nylon 6 resin is improved. It has been found that this effect is particularly large in compositions reinforced with calcined kaolin powder surface-treated with vinyltriethoxysilane, leading to the present invention. That is, the present invention uses 100 parts by weight of a resin mixture consisting of 85 to 99% by weight of nylon 66 resin and 15 to 1% by weight of nylon 6 resin, and 10 to 100 parts by weight of calcined kaolin powder surface-treated with vinyltriethoxysilane. The invention relates to a reinforced polyamide resin composition consisting of a polyamide resin composition, which is suitable as an automobile parts material. The composition of the present invention will be explained below. The nylon 66 resin used in the present invention is a polyamide having 90 mol% or more of hexamethylene adipamide units, and includes other comonomer components such as ε-caprolactam, ω-laurolactam,
Salts of hexamethylene diamine and sebacic acid, salts of hexamethylene diamine and dodecanedioic acid, etc. 10
It may contain less than mol%. Further, these comonomers can be contained alone or in combination of two or more. The molecular weight of the nylon 66 resin is not particularly limited, but includes those within the molecular weight range normally used for producing molded products by injection molding or the like. Nylon 6 resin, which is the second constituent resin used in the present invention, is a polyamide having 90 mol% or more of caprolactam units, and other comonomer components include ω-laurolactam, hexamethylene diamine, and a salt of adipic acid. , a salt of hexamethylene diamine and dodecanedioic acid, or the like may be contained in an amount of less than 10 mol %. This nylon 6
The molecular weight of the resin is also not particularly limited, and it is preferably within a molecular weight range that can be molded under normal molding conditions. In the present invention, nylon 66 resin and nylon 6
The mixing ratio with the resin is 85 to 99% by weight of nylon 66 resin and 15 to 1% by weight of nylon 6 resin. If the mixing ratio of nylon 66 resin is less than 85% by weight, the heat resistance and rigidity will decrease, and if it is more than 99% by weight, there will be little effect of improving the falling weight impact strength. The blending ratio is particularly preferably 90 to 97% by weight. The calcined kaolin powder described in the present invention is obtained by calcining the kaolin viscosity in the temperature range of 350 to 1000° C. for several hours and then pulverizing it, and preferably has an average particle size of 10 μm or less, particularly 2 μm or less. This calcined kaolin is surface-treated with vinyltriethoxysilane and used in the present invention. The blending amount of the calcined kaolin powder surface-treated with vinyltriethoxysilane used in the present invention is 10 to 100 parts by weight based on 100 parts by weight of the resin mixture consisting of nylon 66 resin and nylon 6 resin, and 10 parts by weight. If it exceeds 100 parts by weight, the reinforcing effect will be insufficient, and if it exceeds 100 parts by weight, the fluidity during molding will decrease, making workability in the molding process difficult. Further, the degree of wear and tear on the machinery used increases, and furthermore, it becomes difficult to obtain a uniform mixing and dispersion state, and the surface condition of the molded product deteriorates, which is undesirable. The preparation of the reinforced polyamide resin composition of the present invention includes
This is carried out by conventional methods for preparing polyamide compositions. For example, nylon 66 resin, nylon 6 resin, and calcined kaolin powder surface-treated with vinyltriethoxysilane are premixed, this is fed to an extruder, melted and kneaded, and then cooled and pelletized. Examples include a method of dry blending nylon 6 resin with reinforced nylon 66 resin containing inorganic mineral powder and molding the resin. The reinforced polyamide resin composition of the present invention may contain other ingredients as long as they do not impair its moldability and physical properties, such as pigments, dyes, heat resistant agents, oxidative deterioration inhibitors, lubricants, twist retardants, and antistatic agents. , mold release agents, plasticizers, other resin polymers, fibrous reinforcing materials, etc. can be added. Hereinafter, the present invention will be explained in more detail with reference to Examples. The physical properties of the test pieces described in Examples and Comparative Examples were measured in accordance with the following method. (1) Tensile test: ASTM D638 (2) Bending test: ASTM D790 (3) Heat distortion temperature: ASTM D648 (4) Fall weight impact strength: JIS K7211 Example 1 Nylon 66 with a relative viscosity of 2.80; relative to 95 parts by weight 5 parts by weight of nylon 6 with a viscosity of 2.75 and 67 parts by weight of calcined kaolin (manufactured by ENGEL HARD: Satintone No. 1) surface-treated with vinyltriethoxysilane (KBE1003 manufactured by Shin-Etsu Silicon) were premixed in a V-type blender. Then, using a 70 mmφ single screw extruder, the mixture was melt-mixed at 290°C and cooled to obtain pellets. The obtained pellets are molded using an injection molding machine.
It was molded into a test piece for measuring physical properties at a temperature of 290°C, and various physical properties were evaluated. The results are shown in Table 1. Example 2 Test pieces for measuring physical properties were molded in exactly the same manner as in Example 1, except that 90 parts by weight of nylon 66 and 10 parts by weight of nylon 6 were used, and various physical properties were evaluated. The results are shown in Table 1. Example 3 Test pieces for measuring physical properties were molded in exactly the same manner as in Example 1, except that nylon 66 was used as 98 parts by weight and nylon 6 was used as 2 parts by weight, and various physical properties were evaluated. The results are shown in Table 1. Example 4 Test pieces for measuring physical properties were molded in exactly the same manner as in Example 1, except that nylon 66: 87 parts by weight and nylon 6: 13 parts by weight were used, and various physical properties were evaluated. The results are shown in Table 1. Comparative Example 1 Test pieces for measuring physical properties were molded in exactly the same manner as in Example 1, except that nylon 66 was 80 parts by weight and nylon 6 was 20 parts by weight, and various physical properties were evaluated. The results are shown in Table 1. Comparative Example 2 A test piece for measuring physical properties was molded in exactly the same manner as in Example 1 except that 100 parts by weight of nylon 66 was used and nylon 6 was not used, and various physical properties were evaluated. The results are shown in Table 1. Comparative Example 3 A test piece for measuring physical properties was molded in the same manner as in Example 1 except that 150 parts by weight of calcined kaolin was used.
Various physical properties were evaluated. The results are shown in Table 1. Comparative Example 4 A test piece for measuring physical properties was molded in the same manner as in Example 1 except that the calcined kaolin was changed to 5.3 parts by weight.
Various physical properties were evaluated. The results are shown in Table 1. Comparative Example 5 Kaolin (ENGEL) was used instead of calcined kaolin.
A test piece for measuring physical properties was molded in exactly the same manner as in Example 1, except that ASP200 manufactured by HARD was used, and various physical properties were evaluated. The results are shown in Table 1. Comparative Example 6 Physical properties were obtained in exactly the same manner as in Example 1, except that 95 parts by weight of nylon 66 with a relative viscosity of 2.80, 5 parts by weight of nylon 6 with a relative viscosity of 2.75, and 50 parts by weight of glass fiber (MA416 manufactured by Asahi Fiber Glass) were used. Test pieces for measurement were molded and various physical properties were evaluated. The results are shown in Table 1. Comparative Example 7 A test piece for measuring physical properties was molded in exactly the same manner as in Comparative Example 6, except that nylon 66 was used at 100 parts by weight and nylon 6 was not used, and various physical properties were evaluated. The results are shown in Table 1.
【表】【table】
【表】【table】