JP2004107531A - Chlorinated vinyl chloride resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a chlorinated vinyl chloride resin composition which is excellent in heat stability and can give a molded article excellent in transparency. <P>SOLUTION: The chlorinated vinyl chloride resin composition comprises: 100 pts.wt. of a chlorinated vinyl chloride resin; 1-7 pts.wt. of a liquid stabilizer comprising an organic mercapto compound which consists of (a) 5-50 wt.% of a dialkyltinbis(mercaptofatty acid ester) represented by general formula (1), (b) 10-50 wt.% of a mercaptofatty acid ester represented by general formula (2), and (c) 30-75 wt.% of an oily substance separated from a product obtained by adding hydrochloric acid to a dialkyltinbis(mercaptofatty acid ester) represented by general formula (1) and subjecting the mixture to heat treatment; and 0.1-2 pts.wt. of a dialkyltin malate polymer represented by general formula (3). <P>COPYRIGHT: (C)2004,JPO

Description

（式中、Ｒ^１，Ｒ^２は炭素数１〜１６個のアルキル基、Ｒ^３，Ｒ^４は炭素数１〜１８個のアルキル基、ｍは１又は２を示す）
【００１１】
【化５】

（式中、Ｒ^５は炭素数１〜１８個のアルキル基又は炭素数１〜５のアルコキシアルキル基、ｎは１又は２を示す）
【００１２】
【化６】

（式中、Ｒ^６は炭素数１〜１８個のアルキル基、ｐ　は２〜４の整数を示す）
【００１３】
本発明で使用される塩素化塩化ビニル系樹脂は、塩化ビニル系樹脂が塩素化されたものであり、塩素化度は小さいと難燃性が不十分になり、大きいと熱成形性が低下するので、塩素含有量は６４〜７０重量％が好ましく、より好ましくは６４〜６７重量％である。
【００１４】
上記塩化ビニル系樹脂としては、塩化ビニル単独重合体または塩化ビニルを主成分とし、塩化ビニルモノマーと共重合可能なモノマーや重合体との共重合体が挙げられる。これらは単独で用いられても良く、２種類以上併用して用いても良い。
【００１５】
上記塩化ビニルモノマーと共重合可能なモノマーとしては、例えば、エチレン、プロピレン、ブチレン等のα−オレフィン類；プロピオン酸ビニル等のビニルエステル類；エチルビニルエーテル、ブチルビニルエーテル等のビニルエーテル類；メチル（メタ）アクリレート、ブチル（メタ）アクリレート、ヒドロキシエチル（メタ）アクリレート等の（メタ）アクリレート類；スチレン、α−メチルスチレン等の芳香族ビニル類；フッ化ビニル、フッ化ビニリデン、塩化ビニリデン等のハロゲン化ビニル類；Ｎ−フェニルマレイミド、Ｎ−シクロヘキシルマレイミド等のＮ−置換マレイミド類等が挙げられる。これらのその他の共重合性モノマーは、単独で用いられても良いし、２種類以上が併用されても良い。
【００１６】
又、上記塩化ビニルモノマーと共重合可能な重合体としては、例えば、アルキル（メタ）アクリレートモノマーなどからなるアクリル系共重合体等が挙げられ、これらのその他の共重合性重合体は、単独で用いられても良いし、２種類以上が併用されても良い。
尚、ここで言う（メタ）アクリレートとはアクリレート又はメタクリレートを意味する。
【００１７】
塩化ビニルモノマーと、上記その他の共重合性モノマーや重合体とを併用する場合、その他の共重合性モノマーや重合体の使用量は、塩化ビニル系樹脂に付与したい性能や目的に応じて適宜設定されれば良く、特に限定されるものではない。
【００１８】
上記塩化ビニル系樹脂は、平均重合度が４００〜８００の塩化ビニル系樹脂が好ましい。平均重合度は小さくなると機械的物性が低下し、大きくなると熱流動性が低下し、成形しにくくなるので、４００〜８００が好ましく、より好ましくは５００〜７００である。
【００１９】
尚、上記平均重合度とは、塩化ビニル単独重合体や塩化ビニル系共重合体をテトラヒドロフラン（ＴＨＦ）に溶解させ、濾過により不溶成分を除去した後、濾液中のＴＨＦを乾燥除去して得た樹脂を試料とし、ＪＩＳ　Ｋ−６７２１「塩化ビニル樹脂試験方法」に準拠して測定した平均重合度を意味する。
【００２０】
上記塩素化は従来公知の任意の方法が採用されて良く、例えば、上記塩化ビニル系樹脂を水に懸濁させ、塩素ガスを導入し、紫外線照射や加熱により塩素化する方法、塩化ビニル系樹脂を有機溶剤に溶解し、塩素を導入して塩素化する方法、粉末状態の塩化ビニル系樹脂に塩素ガスを接触させて塩素化する方法が挙げられ、水懸濁で塩素化する方法が、透明性、耐熱性及び熱成形性が優れているので好ましく、又、光照射することなく６０〜１４０℃に加熱して塩素化する方法が好ましい。
【００２１】
上記塩化ビニル系樹脂に光照射することなく、６０〜１４０℃で塩素化反応する方法は、光照射しない以外は、従来公知の塩化ビニル系樹脂の塩素化方法が採用されてよい。
【００２２】
即ち、例えば、密閉可能な反応容器内に塩化ビニル系樹脂を水性媒体に懸濁させ、反応容器内を減圧した後、塩素を反応容器内に導入し、塩化ビニル系樹脂を塩素化する方法であって、塩素化の際に光照射せず、６０〜１４０℃に加熱して、熱により塩素化する。
【００２３】
上記反応容器内の減圧条件は、酸素が多量に存在すると、得られた塩素化塩化ビニル系樹脂の熱安定性が低下するので、反応容器内の酸素残存量が１００ｐｐｍ以下になるように減圧されるのが好ましい。
【００２４】
塩素は、反応容器内を減圧した後、反応容器内に導入されるが、塩素に酸素が多量に含まれていると得られた塩素化塩化ビニル系樹脂の熱安定性が低下するので、酸素含有量が１００ｐｐｍ以下の塩素を用いるのが好ましい。
【００２５】
塩素の導入量は、少なくなると塩素化反応が進みにくくなり、多くなると高価な反応容器が必要となり、コスト的に不利になるので、反応容器内の塩素分圧で０．１〜１．０ＭＰａが好ましく、より好ましくは０．２〜０．５ＭＰａである。尚、塩素分圧は、塩素化反応中一定であってもよいし、塩素化反応の進行につれて段階的に高くしてもよい。
【００２６】
上記加熱温度は、低くなると塩素化反応が遅くなり、高くなると反応中に脱塩酸反応がおこるようになり、得られた塩素化塩化ビニル系樹脂の熱安定性が低下するので、６０〜１４０℃であり、好ましくは７０〜１３０℃である。
【００２７】
又、塩素化反応を促進し、より熱安定性の優れた塩素化塩化ビニル系樹脂を得るために、塩素化反応中に過酸化水素が添加されるのが好ましい。
【００２８】
上記過酸化水素は純水なものでもよいが、取り扱いしやすい水溶液が好適に使用される。過酸化水素の添加量は、少なくなると塩素化反応促進効果が得られず、多くなると得られた塩素化塩化ビニル系樹脂の熱安定性が低下するので、塩化ビニル系樹脂に対し４〜５０ｐｐｍ／ｈｒが好ましく、より好ましくは５〜３０ｐｐｍ／ｈｒである。
【００２９】
上記過酸化水素の添加方法は公知の任意の方法が採用されてよく、例えば、初期一括添加方法、間欠的添加方法、連続的添加方法等が挙げられる。又、添加時期も適宜決定されればよいが、塩化ビニル系樹脂の塩素含有量が６０重量％以上になった時点から添加すると、塩素化反応が安定して進み、熱安定性の優れた塩素化塩化ビニル系樹脂が得られるので好ましい。
【００３０】
本発明で使用される有機メルカプト系液状安定剤は、（ａ）ジアルキル錫ビス（メルカプト脂肪酸エステル）、（ｂ）メルカプト脂肪酸エステル及び（ｃ）ジアルキル錫ビス（メルカプト脂肪酸エステル）に塩酸を加えて加熱処理し、得られた生成物から分離した油状物質よりなる。
【００３１】
上記（ａ）ジアルキル錫ビス（メルカプト脂肪酸エステル）は、下記一般式（１）で表される化合物であり、式中、Ｒ^１，Ｒ^２は炭素数１〜１６個のアルキル基、Ｒ^３，Ｒ^４は炭素数１〜１８個のアルキル基、ｍは１又は２を示す。
【００３２】
【化７】

【００３３】
上記（ａ）ジアルキル錫ビス（メルカプト脂肪酸エステル）としては、例えば、ジアルキル錫ビス（イソオクチルメルカプトアセテート）、ジアルキル錫ビス（２−エチルヘキシルメルカプトアセテート）、ジアルキル錫ビス（ドデシルメルカプトアセテート）、ジアルキル錫ビス（オクタデシルメルカプトアセテート）、ジアルキル錫ビス（ステアリルメルカプトアセテート）、ジアルキル錫ビス（２−エチルヘキシルメルカプトプロピオネート）、ジアルキル錫ビス（メトキシブチルメルカプトプロピオネート）等が挙げられ、ここで、ジアルキル錫としては、ジメチル錫、ジブチル錫、ジオクチル錫、ジドデシル錫等が挙げられる。
【００３４】
上記（ｂ）メルカプト脂肪酸エステルは、下記一般式（２）で表される化合物であり、式中、Ｒ^５は炭素数１〜１８個のアルキル基又は炭素数１〜５のアルコキシアルキル基、ｎは１又は２を示す。
【００３５】
【化８】

【００３６】
上記（ｂ）メルカプト脂肪酸エステルとしては、例えば、メルカプト酢酸メチルエステル、メルカプト酢酸ブチルエステル、メルカプト酢酸２−エチルヘキシルエステル、メルカプト酢酸イソオクチルエステル、メルカプト酢酸デシルエステル、メルカプト酢酸ドデシルエステル、メルカプト酢酸ステアリルエステル、メルカプト酢酸ヘキサデシルエステル、メルカプト酢酸オクタデシルエステル、メルカプト酢酸オレイルエステル、メルカプト酢酸メトキシブチルエステル、メルカプトプロピオン酸２−エチルヘイキシルエステル、メルカプトプロピオン酸イソオクチルエステル、メルカプトプロピオン酸ノニルエステル等が挙げられる。
【００３７】
上記（ｃ）油状物質は、上記一般式（１）で表されるジアルキル錫ビス（メルカプト脂肪酸エステル）に塩酸を加えて加熱処理し、得られた生成物から分離した油状物質である。
【００３８】
塩酸の添加量は、特に限定されるものではないが、一般式（１）で表されるジアルキル錫ビス（メルカプト脂肪酸エステル）１モルに対し０．２〜３モルが好ましい。
【００３９】
加熱処理温度は１００〜３００℃が好ましく、より好ましくは１５０〜２００℃であり、加熱処理時間は５〜１２０分が好ましく、加熱処理温度が高い場合は処理時間を短くし、低い場合は長くすればよい。従って、加熱処理温度が１５０〜２００℃で１０〜６０分処理するのがより好ましい。
【００４０】
一般式（１）で表されるジアルキル錫ビス（メルカプト脂肪酸エステル）は水に溶解せず、比重が１以下なので水に浮かんでいるが、上記加熱処理をすると塩酸と反応して生成した水溶性物質は水に溶解し、非水溶性物質は油状物質として水の上に液層を形成する。本発明ではこの油状物質を熱安定剤として使用する。
【００４１】
本発明で使用される有機メルカプト系液状安定剤は、上記（ａ）ジアルキル錫ビス（メルカプト脂肪酸エステル）、（ｂ）メルカプト脂肪酸エステル及び（ｃ）油状物質よりなるが、その配合比率は（ａ）ジアルキル錫ビス（メルカプト脂肪酸エステル）５〜５０重量％、（ｂ）メルカプト脂肪酸エステルが１０〜５０重量％、（ｃ）油状物質が３０〜７５重量％である。
【００４２】
上記有機メルカプト系液状安定剤の添加量は、少ないと熱安定性が向上せず、熱成形の際に塩素化塩化ビニル系樹脂が分解し成形できなくなったり、黄変して透明性が低下したりし、多いと耐熱性、難燃性等が低下し、着色するようになるので、塩素化塩化ビニル系樹脂組成物１００重量部に対し１〜７重量部添加されるのである。
【００４３】
本発明で使用されるジアルキル錫マレートポリマーは、下記一般式（３）で表される２３℃で固体の熱安定剤であり、式中、Ｒ^６は炭素数１〜１８個のアルキル基、ｐ　は２〜４の整数を示す。
【００４４】
【化９】

【００４５】
上記ジアルキル有機錫マレ−トポリマーとしては、例えば、ジメチル錫マレートポリマー、ジブチル錫マレートポリマー、ジオクチル錫マレートポリマー等が挙げられる。
【００４６】
上記ジアルキル錫マレートポリマーは、添加量が少ないと熱安定性が向上せず、熱成形の際に塩素化塩化ビニル系樹脂が分解し成形できなくなったり、黄変して透明性が低下したりし、多いと安定剤による着色が発生し透明性が低下するので、塩素化塩化ビニル系樹脂組成物１００重量部に対し０．１〜２重量部添加される。
【００４７】
本発明の塩素化塩化ビニル系樹脂組成物には、本発明の目的を損なわない範囲で、必要に応じて、塩化ビニル系樹脂成形体の製造の際に一般に使用されている熱安定剤、安定化助剤、改質剤、加工助剤、滑剤、酸化防止剤、光安定剤、紫外線吸収剤、帯電防止剤、顔料、充填剤、可塑剤等の配合剤が添加されてもよい。
【００４８】
上記熱安定剤としては、塩化ビニル系樹脂成形体の製造の際に一般に使用されている熱安定剤であれば特に限定されず、例えば、ステアリン酸鉛、二塩基性亜リン酸鉛、三塩基性硫酸鉛等の鉛系安定剤、カルシウム−亜鉛系安定剤、バリウム−亜鉛系安定剤、バリウム−カドミウム系安定剤等が挙げられる。これらは単独で用いてもよく、２種以上を併用してもよい。
【００４９】
上記安定化助剤としては、塩化ビニル系樹脂成形体の製造の際に一般に使用されている安定化助剤であれば特に限定されず、例えば、エポキシ化大豆油、エポキシ化アマニ豆油、エポキシ化テトラヒドロフタレート、エポキシ化ポリブタジエン、リン酸エステル等が挙げられる。これらは単独で用いてもよく、２種以上を併用してもよい。
【００５０】
上記改質剤としては、塩化ビニル系樹脂成形体の製造の際に一般に使用されている安定化助剤であれば特に限定されず、例えば、メチルメタクリレート−ブタジエンースチレン共重合体（ＭＢＳ樹脂）等が挙げられる。これらは単独で用いてもよく、２種以上を併用してもよく、その添加量は衝撃改質効果と難燃性のバランスから塩化ビニル系樹脂組成物１００重量部に対し１〜１５重量部が好ましい。
【００５１】
上記加工助剤としては、塩化ビニル系樹脂成形体の製造の際に一般に使用されている加工助剤であれば特に限定されず、例えば、重量平均分子量３万〜５００万のアルキルアクリレート−アルキルメタクリレート共重合体、アルキルアクリレート−アルキルメタクリレート−スチレン共重合体等のアクリル系加工助剤が挙げられ、具体例としては、ｎ−ブチルアクリレート−メチルメタクリレート共重合体、２−エチルヘキシルアクリレート−メチルメタクリレート−ブチルメタクリレート共重合体等が挙げられる。これらは単独で用いてもよく、２種以上を併用してもよい。
【００５２】
上記滑剤としては、内部滑剤、外部滑剤等が挙げられる。
上記内部滑剤は、成形加工時の溶融樹脂の流動粘度を下げ、摩擦発熱を防止する目的で使用される。上記内部滑剤としては、塩化ビニル系樹脂成形体の製造の際に一般に使用されている内部滑剤であれば特に限定されず、例えば、ブチルステアレート、ラウリルアルコール、ステアリルステアレート、エポキシ化大豆油、グリセリンモノステアレート、ステアリン酸、ビスアミド等が挙げられる。これらは単独で用いてもよく、２種以上を併用してもよい。
【００５３】
上記外部滑剤は、成形加工時の溶融樹脂と金属面との滑り効果を上げる目的で使用される。上記外部滑剤としては、塩化ビニル系樹脂成形体の製造の際に一般に使用されている外部滑剤であれば特に限定されず、例えば、モンタン酸ワックス、パラフィンワックス、ポリオレフィンワックス、エステルワックス等が挙げられる。これらは単独で用いてもよく、２種以上を併用してもよい。
【００５４】
上記酸化防止剤としては、塩化ビニル系樹脂成形体の製造の際に一般に使用されている酸化防止剤であれば特に限定されず、例えば、フェノール系抗酸化剤、硫黄系抗酸化剤、ホスファイト系抗酸化剤等が挙げられる。これらは単独で用いてもよく、２種以上を併用してもよい。
【００５５】
上記光安定剤としては、塩化ビニル系樹脂成形体の製造の際に一般に使用されている光安定剤であれば特に限定されず、例えば、ヒンダードアミン系の光安定剤等が挙げられる。これらは単独で用いてもよく、２種以上を併用してもよい。
【００５６】
上記紫外線吸収剤としては、塩化ビニル系樹脂成形体の製造の際に一般に使用されている紫外線吸収剤であれば特に限定されず、例えば、サリチル酸エステル系、ベンゾフェノン系、ベンゾトリアゾール系、シアノアクリレート系等の紫外線吸収剤が挙げられる。これらは単独で用いてもよく、２種以上を併用してもよい。
【００５７】
上記帯電防止剤としては、塩化ビニル系樹脂成形体の製造の際に一般に使用されている帯電防止剤であれば特に限定されず、例えば、カチオン系帯電防止剤、非イオン系帯電防止剤等が挙げられる。これらは単独で用いてもよく、２種以上を併用してもよい。
【００５８】
上記顔料としては、塩化ビニル系樹脂成形体の製造の際に一般に使用されている顔料であれば特に限定されず、例えば、アゾ系、フタロシアニン系、スレン系、染料レーキ系等の有機顔料、酸化物系、クロム酸モリブデン系、硫化物・セレン化物系、フェロシアン化物系等の無機顔料等が挙げられる。これらは単独で用いてもよく、２種以上を併用してもよい。
【００５９】
上記充填剤としては、塩化ビニル系樹脂成形体の製造の際に一般に使用されている充填剤であれば特に限定されず、例えば、炭酸カルシウム、炭酸マグネシウム、酸化アルミニウム、酸化マグネシウム、酸化チタン、水酸化マグネシウム、タルク、マイカ、クレー、フライアッシュ等が挙げられる。これらは単独で用いてもよく、２種以上を併用してもよい。
【００６０】
上記可塑剤としては、塩化ビニル系樹脂成形体の製造の際に一般に使用されている充填剤であれば特に限定されず、例えば、ジブチルフタレート、ジ−２−エチルヘキシルフタレート、ジ−２−エチルヘキシルアジペート等が挙げられる。これらは単独で用いてもよく、２種以上を併用してもよい。
【００６１】
塩素化塩化ビニル系樹脂に上記有機メルカプト系液状安定剤、ジアルキル錫マレートポリマー及び各種配合剤を混合する方法は、特に限定されず、例えば、ヘンシェルミキサー、スパーミキサー、リボンブレンダー等で混合すればよく、混合はホットブレンド法でもコールドブレンド法でもよいが、液状の熱安定剤や可塑剤、滑剤等を添加する場合はホットブレンド法が好ましい。
【００６２】
本発明の塩素化塩化ビニル系樹脂組成物から成形体を製造する方法は、従来公知の任意の方法が採用されて良く、例えば、単軸押出機、異方向二軸押出機、コニカル二軸押出機等の押出機で押出成形する方法、プレス成形法、射出成形法等が挙げらる。
【００６３】
【発明の実施の形態】
以下に実施例を挙げて、具体的に本発明の効果を説明するが、本発明はこれら実施例のみに限定されるものではない。
【００６４】
（実施例１〜８、比較例１〜４）
塩素化塩化ビニル樹脂（１）の合成
グラスライニング製反応器に、脱イオン水２００重量部と懸濁重合法で製造された塩化ビニル樹脂（平均重合度６００、平均粒子径１５０μｍ）４０重量部を供給し、攪拌しながら６０℃に昇温した。
【００６５】
次に、反応器内を真空にして酸素を除去した後、塩素ガスを塩素分圧が０．２ＭＰａになるよう導入し、紫外線を照射して塩素化反応を開始した。塩素化反応中は反応温度を６０℃、塩素分圧を０．２ＭＰａに保ち、塩素化塩化ビニル樹脂の塩素含有量が６５．０重量％に達した時点で塩素ガスの供給及び紫外線照射を停止し塩素化反応を終了した。
【００６６】
反応終了後、窒素ガスを供給し、未反応塩素ガスを除去し、得られたスラリ−を水洗、脱水、乾燥して粉末状の塩素化塩化ビニル樹脂（１）を得た。
【００６７】
塩素化塩化ビニル樹脂（２）の合成
グラスライニング製反応器に、脱イオン水２００重量部と懸濁重合法で製造された塩化ビニル樹脂（平均重合度６００、平均粒子径１５０μｍ）４０重量部を供給し、攪拌しながら７０℃に昇温した。
【００６８】
次に、反応器内を真空にして酸素を除去した後、塩素ガスを塩素分圧が０．５ＭＰａになるよう導入し、更に加熱して１１０℃まで昇温して塩素化反応を行った。
【００６９】
又、塩素分圧が０．５ＭＰａに達した時点から塩素化塩化ビニル樹脂の塩素含有量が６５．０重量％に達する１時間前まで塩化ビニル樹脂に対し５ｐｐｍ／ｈｒの速度で過酸化水素を連続的に添加した。
【００７０】
塩素化反応中は反応温度を１１０℃、塩素分圧を０．５ＭＰａに保ち、塩素化塩化ビニル樹脂の塩素含有量が６５．０重量％に達した時点で塩素ガスの供給を停止し冷却して塩素化反応を終了した。
【００７１】
反応終了後、窒素ガスを供給し、未反応塩素ガスを除去し、得られたスラリ−を水洗、脱水、乾燥して粉末状の塩素化塩化ビニル樹脂（２）を得た。
【００７２】
油状物質（ｃ）の作製
ジ−ｎ−オクチル錫ビス（イソオクチルメルカプトアセテート）１モルと塩酸１モルをコンデンサー付きフラスコに供給し、１５０℃で６０分間加熱した。加熱終了後冷却し、上層の油状物質を分離水洗して油状物質（ｃ）を得た。
【００７３】
有機メルカプト系液状安定剤の調製
表１に示した所定量の油状物質（ｃ）並びにジブチル錫ビス（イソオクチルメルカプトアセテート）、ジブチル錫ビス（ステアリルメルカプトアセテート）、メルカプト酢酸ステアリルエステル及びメルカプト酢酸イソオクチルエステルを混合して有機メルカプト系液状安定剤を得た。
【００７４】
塩素化塩化ビニル系樹脂成形板の作製
表２に示した所定量の塩素化塩化ビニル樹脂（１）、（２）、有機メルカプト系液状安定剤及びジブチル錫マレートポリマー並びにＭＢＳ樹脂（三菱レーヨン社製、商品名「Ｃ−１５０Ｓ」）５重量部及び滑剤（コグニスジャパン社製、商品名「Ｇ６０」）１重量部を８インチロールに供給し、１９０℃で３分間混練してロールシートを得た。
【００７５】
得られたロールシートを１９０℃で３分間予熱した後、１９０℃で４分間、面圧７５ｋｇ／ｃｍ^２で加圧プレスし、冷却して、厚さ２ｍｍの塩素化塩化ビニル系樹脂成形板を得た。
【００７６】
塩素化塩化ビニル系樹脂成形板の物性評価
上記で得られた塩化ビニル系樹脂成形板及びロールシートについて、下記物性を測定し、その結果を表２に示した。
【００７７】
（１）熱安定性　８インチロールで混練して得られたロールシートを１９０℃のギアオーブンに静置し、黒化するまでの時間（分）を測定した。
（２）黄色度　得られた２ｍｍ厚みの塩素化塩化ビニル系樹脂成形板をＪＩＳ
Ｋ７１０５に準拠して測定した。
【００７８】
（３）全光線透過率　得られた２ｍｍ厚みの塩素化塩化ビニル系樹脂成形板をＪＩＳ　Ｋ７３６１−１に準拠して測定した。
【００７９】
【表１】

【００８０】
【表２】

【００８１】
【発明の効果】
本発明の塩素化塩化ビニル系樹脂組成物の構成は、上述の通り、塩素化塩化ビニル系樹脂１００重量部に、（ａ）一般式（１）で表されるジアルキル錫ビス（メルカプト脂肪酸エステル）５〜５０重量％、（ｂ）一般式（２）で表されるメルカプト脂肪酸エステル１０〜５０重量％及び（ｃ）一般式（１）で表されるジアルキル錫ビス（メルカプト脂肪酸エステル）に塩酸を加えて加熱処理し、得られた生成物から分離した油状物質３０〜７５重量％よりなる有機メルカプト系液状安定剤１〜７重量部と、一般式（３）で表されるジアルキル錫マレートポリマー０．１〜２重量部を添加してなるので、熱安定性が優れており、容易に熱成形することができ、初期着色性が優れている。
【００８２】
従って、本発明の塩素化塩化ビニル系樹脂組成物から得られた成形体は透明性、難燃性が優れており、本来の塩素化塩化ビニル系樹脂の長所である機械的強度、　耐薬品性、二次加工性等を併せ持つので、電子部品ケース、食品容器等として好適に使用できる。
【００８３】
更に、塩素化塩化ビニル系樹脂として塩化ビニル系樹脂が光照射することなく、６０〜１４０℃で熱塩素化された塩素化塩化ビニル系樹脂を使用すると、初期着色性と熱安定性がより優れており、透明性のより優れた成形体が得られる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a chlorinated vinyl chloride resin composition.
[0002]
[Prior art]
Chlorinated vinyl chloride resin has higher heat resistance than vinyl chloride resin and is excellent in mechanical strength, chemical resistance, flame retardancy, etc., so it is expected to be used for electronic parts cases and food containers etc. Have been.
[0003]
However, the chlorinated vinyl chloride resin, like the vinyl chloride resin, is deteriorated and colored by heat and light, and gradually decomposes to black, so that it has been difficult to develop a transparent product.
[0004]
In order to solve such problems, for example, a stabilization method has been proposed in which an oil obtained by heat-treating organotin bis (mercapto fatty acid ester) and hydrochloric acid is added to a chlorinated vinyl chloride resin. (For example, see Patent Document 1)
[0005]
Also disclosed is a stabilized chlorinated vinyl chloride resin composition in which an alkyltin mercapto fatty acid ester and an alkyltin chloride or / and mercaptocarboxylic acid ester are added to a chlorinated vinyl chloride resin. (For example, see Patent Document 2)
[0006]
However, the thermal stability of the chlorinated vinyl chloride resin composition is still insufficient, and it is difficult to obtain a transparent product by decomposing at the time of thermoforming and causing initial coloring.
[0007]
[Patent Document 1]
JP-A-63-248838 (pages 1 to 5)
[Patent Document 2]
Japanese Patent Publication No. 2-51935 (pages 1 to 5)
[0008]
[Problems to be solved by the invention]
The present invention provides a chlorinated vinyl chloride resin composition which has excellent thermal stability in view of the above-mentioned drawbacks, does not undergo initial coloring during thermoforming, and is capable of obtaining a molded article having excellent transparency. The purpose is to do.
[0009]
[Means for Solving the Problems]
The chlorinated vinyl chloride-based resin composition of the present invention comprises 100 parts by weight of a chlorinated vinyl chloride-based resin, (a) 5 to 50% by weight of a dialkyltin bis (mercapto fatty acid ester) represented by the general formula (1), (B) 10 to 50% by weight of a mercapto fatty acid ester represented by the general formula (2) and (c) dialkyltin bis (mercapto fatty acid ester) represented by the general formula (1) are heated by adding hydrochloric acid thereto, 1 to 7 parts by weight of an organic mercapto-based liquid stabilizer consisting of 30 to 75% by weight of an oily substance separated from the obtained product, and 0.1 to 2 parts by weight of a dialkyltin maleate polymer represented by the general formula (3) It is characterized by comprising a part.
[0010]
Embedded image

(In the formula, R ¹ and R ² represent an alkyl group having 1 to 16 carbon atoms, R ³ and R ⁴ represent an alkyl group having 1 to 18 carbon atoms, and m represents 1 or 2.)
[0011]
Embedded image

(Wherein, R ⁵ represents an alkyl group having 1 to 18 carbon atoms or an alkoxyalkyl group having 1 to 5 carbon atoms, and n represents 1 or 2)
[0012]
Embedded image

(Wherein, R ⁶ represents an alkyl group having 1 to 18 carbon atoms, and p represents an integer of 2 to 4)
[0013]
The chlorinated vinyl chloride resin used in the present invention is obtained by chlorinating a vinyl chloride resin.If the chlorination degree is small, the flame retardancy becomes insufficient, and if the chlorination degree is large, the thermoformability decreases. Therefore, the chlorine content is preferably from 64 to 70% by weight, more preferably from 64 to 67% by weight.
[0014]
Examples of the vinyl chloride resin include a vinyl chloride homopolymer or a copolymer containing vinyl chloride as a main component and a monomer or polymer copolymerizable with a vinyl chloride monomer. These may be used alone or in combination of two or more.
[0015]
Examples of the monomer copolymerizable with the vinyl chloride monomer include α-olefins such as ethylene, propylene and butylene; vinyl esters such as vinyl propionate; vinyl ethers such as ethyl vinyl ether and butyl vinyl ether; methyl (meth) (Meth) acrylates such as acrylate, butyl (meth) acrylate and hydroxyethyl (meth) acrylate; aromatic vinyls such as styrene and α-methylstyrene; vinyl halides such as vinyl fluoride, vinylidene fluoride and vinylidene chloride And N-substituted maleimides such as N-phenylmaleimide and N-cyclohexylmaleimide. These other copolymerizable monomers may be used alone or in combination of two or more.
[0016]
Examples of the polymer copolymerizable with the vinyl chloride monomer include an acrylic copolymer composed of an alkyl (meth) acrylate monomer and the like. These other copolymerizable polymers may be used alone. They may be used, or two or more kinds may be used in combination.
In addition, (meth) acrylate here means acrylate or methacrylate.
[0017]
When the vinyl chloride monomer and the other copolymerizable monomer or polymer are used in combination, the amount of the other copolymerizable monomer or polymer used is appropriately set according to the performance or purpose to be imparted to the vinyl chloride resin. It should just be done, and it is not particularly limited.
[0018]
The vinyl chloride resin is preferably a vinyl chloride resin having an average degree of polymerization of 400 to 800. When the average polymerization degree is small, the mechanical properties are reduced, and when the average polymerization degree is large, the thermal fluidity is reduced and molding becomes difficult. Therefore, the average polymerization degree is preferably from 400 to 800, more preferably from 500 to 700.
[0019]
The average polymerization degree was obtained by dissolving a vinyl chloride homopolymer or a vinyl chloride-based copolymer in tetrahydrofuran (THF), removing insoluble components by filtration, and drying and removing THF in the filtrate. It means the average degree of polymerization measured using a resin as a sample and according to JIS K-6721 “Testing method for vinyl chloride resin”.
[0020]
For the chlorination, any conventionally known method may be adopted, for example, a method of suspending the vinyl chloride resin in water, introducing chlorine gas, chlorinating by ultraviolet irradiation or heating, a vinyl chloride resin Is dissolved in an organic solvent and chlorinated by introducing chlorine, a method of chlorinating by contacting chlorine gas with a vinyl chloride resin in a powder state, and a method of chlorinating with water suspension is transparent. It is preferable because it is excellent in heat resistance, heat resistance and thermoformability, and a method of chlorinating by heating to 60 to 140 ° C. without light irradiation is preferable.
[0021]
As a method of performing a chlorination reaction at 60 to 140 ° C. without irradiating the vinyl chloride resin with light, a conventionally known method of chlorinating a vinyl chloride resin may be adopted, except that the light is not irradiated.
[0022]
That is, for example, a method in which a vinyl chloride resin is suspended in an aqueous medium in a hermetically sealable reaction vessel, and the pressure in the reaction vessel is reduced, then chlorine is introduced into the reaction vessel, and the vinyl chloride resin is chlorinated. Therefore, it is heated to 60 to 140 ° C. without irradiating light during chlorination, and chlorinated by heat.
[0023]
The reduced pressure condition in the reaction vessel is such that when a large amount of oxygen is present, the thermal stability of the obtained chlorinated vinyl chloride resin is reduced, so that the pressure is reduced so that the residual amount of oxygen in the reaction vessel becomes 100 ppm or less. Preferably.
[0024]
Chlorine is introduced into the reaction vessel after depressurizing the inside of the reaction vessel.However, if the chlorine contains a large amount of oxygen, the thermal stability of the obtained chlorinated vinyl chloride resin is reduced. It is preferable to use chlorine having a content of 100 ppm or less.
[0025]
When the introduction amount of chlorine is small, the chlorination reaction is difficult to proceed, and when the amount is large, an expensive reaction vessel is required, which is disadvantageous in terms of cost, so that the partial pressure of chlorine in the reaction vessel is 0.1 to 1.0 MPa. Preferably, it is more preferably 0.2 to 0.5 MPa. The chlorine partial pressure may be constant during the chlorination reaction or may be increased stepwise as the chlorination reaction proceeds.
[0026]
When the heating temperature is lower, the chlorination reaction is slower, and when the heating temperature is higher, a dehydrochlorination reaction occurs during the reaction, and the thermal stability of the obtained chlorinated vinyl chloride resin is reduced. And preferably 70 to 130 ° C.
[0027]
Further, in order to accelerate the chlorination reaction and obtain a chlorinated vinyl chloride resin having more excellent thermal stability, it is preferable to add hydrogen peroxide during the chlorination reaction.
[0028]
The hydrogen peroxide may be pure water, but an aqueous solution that is easy to handle is preferably used. If the amount of added hydrogen peroxide is too small, the effect of accelerating the chlorination reaction cannot be obtained, and if it is too large, the thermal stability of the obtained chlorinated vinyl chloride resin decreases. hr is preferable, and more preferably 5 to 30 ppm / hr.
[0029]
As the method for adding hydrogen peroxide, any known method may be employed, and examples thereof include an initial batch addition method, an intermittent addition method, and a continuous addition method. The timing of addition may be determined as appropriate. However, when the chlorine content of the vinyl chloride-based resin is 60% by weight or more, the chlorination reaction proceeds stably, and chlorine having excellent heat stability is obtained. It is preferable because a vinyl chloride resin can be obtained.
[0030]
The organic mercapto-based liquid stabilizer used in the present invention is prepared by adding hydrochloric acid to (a) dialkyltin bis (mercapto fatty acid ester), (b) mercapto fatty acid ester and (c) dialkyltin bis (mercapto fatty acid ester) and heating the mixture. It consists of an oil which has been separated from the product obtained upon processing.
[0031]
The (a) dialkyltin bis (mercapto fatty acid ester) is a compound represented by the following general formula (1), wherein R ¹ and R ² are an alkyl group having 1 to 16 carbon atoms, R ³ , R ⁴ represents an alkyl group having 1 to 18 carbon atoms, and m represents 1 or 2.
[0032]
Embedded image

[0033]
Examples of the above (a) dialkyltin bis (mercapto fatty acid ester) include dialkyltin bis (isooctyl mercaptoacetate), dialkyltin bis (2-ethylhexylmercaptoacetate), dialkyltin bis (dodecylmercaptoacetate), and dialkyltin bis (Octadecylmercaptoacetate), dialkyltin bis (stearylmercaptoacetate), dialkyltinbis (2-ethylhexylmercaptopropionate), dialkyltinbis (methoxybutylmercaptopropionate) and the like. Examples include dimethyltin, dibutyltin, dioctyltin, didodecyltin and the like.
[0034]
The (b) mercapto fatty acid ester is a compound represented by the following general formula (2), wherein R ⁵ is an alkyl group having 1 to 18 carbon atoms or an alkoxyalkyl group having 1 to 5 carbon atoms, n Represents 1 or 2.
[0035]
Embedded image

[0036]
Examples of the mercapto fatty acid ester (b) include methyl mercaptoacetate, butyl mercaptoacetate, 2-ethylhexyl mercaptoacetate, isooctyl mercaptoacetate, decyl mercaptoacetate, dodecyl mercaptoacetate, stearyl mercaptoacetate, Examples thereof include hexadecyl mercaptoacetate, octadecyl mercaptoacetate, oleyl mercaptoacetate, methoxybutyl mercaptoacetate, 2-ethylhexyl mercaptopropionate, isooctyl mercaptopropionate, and nonyl mercaptopropionate.
[0037]
The oily substance (c) is an oily substance separated from the obtained product by adding hydrochloric acid to the dialkyltin bis (mercapto fatty acid ester) represented by the general formula (1) and subjecting to heat treatment.
[0038]
The amount of hydrochloric acid to be added is not particularly limited, but is preferably 0.2 to 3 mol per 1 mol of dialkyltin bis (mercapto fatty acid ester) represented by the general formula (1).
[0039]
The heat treatment temperature is preferably from 100 to 300 ° C., more preferably from 150 to 200 ° C., and the heat treatment time is preferably from 5 to 120 minutes. If the heat treatment temperature is high, the treatment time is shortened; Just fine. Therefore, it is more preferable to perform the heat treatment at a temperature of 150 to 200 ° C. for 10 to 60 minutes.
[0040]
The dialkyltin bis (mercapto fatty acid ester) represented by the general formula (1) does not dissolve in water and has a specific gravity of 1 or less, and thus floats in water. The substance dissolves in water, and the water-insoluble substance forms a liquid layer on the water as an oily substance. In the present invention, this oily substance is used as a heat stabilizer.
[0041]
The organic mercapto-based liquid stabilizer used in the present invention comprises the above (a) dialkyltin bis (mercaptofatty acid ester), (b) mercaptofatty acid ester and (c) an oily substance, and the compounding ratio thereof is (a) 5 to 50% by weight of dialkyl tin bis (mercapto fatty acid ester), 10 to 50% by weight of (b) mercapto fatty acid ester, and 30 to 75% by weight of (c) oily substance.
[0042]
When the amount of the organic mercapto-based liquid stabilizer is small, the thermal stability does not improve when the amount is small, and the chlorinated vinyl chloride-based resin is decomposed during the thermoforming and cannot be molded, or the yellowing is reduced and the transparency is reduced. If the amount is too large, the heat resistance and the flame retardancy are reduced, and the composition becomes colored. Therefore, 1 to 7 parts by weight is added to 100 parts by weight of the chlorinated vinyl chloride resin composition.
[0043]
The dialkyltin maleate polymer used in the present invention is a heat stabilizer which is a solid at 23 ° C. represented by the following general formula (3), wherein R ⁶ is an alkyl group having 1 to 18 carbon atoms, p shows the integer of 2-4.
[0044]
Embedded image

[0045]
Examples of the dialkyl organic tin maleate polymer include a dimethyltin maleate polymer, a dibutyltin maleate polymer, and a dioctyltin maleate polymer.
[0046]
When the amount of the dialkyltin maleate polymer is small, the thermal stability is not improved, and the chlorinated vinyl chloride-based resin is decomposed during thermoforming and cannot be molded, or yellowish and the transparency is reduced. However, if the amount is too large, coloring due to the stabilizer occurs and the transparency is reduced. Therefore, 0.1 to 2 parts by weight is added to 100 parts by weight of the chlorinated vinyl chloride resin composition.
[0047]
The chlorinated vinyl chloride resin composition of the present invention may contain, as necessary, a heat stabilizer generally used in the production of a vinyl chloride resin molded article, as long as the object of the present invention is not impaired. Compounding agents such as chemical aids, modifiers, processing aids, lubricants, antioxidants, light stabilizers, ultraviolet absorbers, antistatic agents, pigments, fillers, and plasticizers may be added.
[0048]
The heat stabilizer is not particularly limited as long as it is a heat stabilizer generally used in the production of a vinyl chloride resin molded article. Examples thereof include lead stearate, dibasic lead phosphite, and tribasic acid. And lead-based stabilizers such as basic lead sulfate, calcium-zinc-based stabilizers, barium-zinc-based stabilizers, and barium-cadmium-based stabilizers. These may be used alone or in combination of two or more.
[0049]
The stabilizing aid is not particularly limited as long as it is a stabilizing aid generally used in the production of a vinyl chloride-based resin molded article. Examples thereof include epoxidized soybean oil, epoxidized linseed oil, and epoxidized soybean oil. Examples include tetrahydrophthalate, epoxidized polybutadiene, and phosphate ester. These may be used alone or in combination of two or more.
[0050]
The modifier is not particularly limited as long as it is a stabilizing aid generally used in the production of a vinyl chloride resin molded article. For example, a methyl methacrylate-butadiene-styrene copolymer (MBS resin) And the like. These may be used alone or in combination of two or more, and the addition amount thereof is 1 to 15 parts by weight based on 100 parts by weight of the vinyl chloride resin composition in view of the balance between the impact modifying effect and the flame retardancy. Is preferred.
[0051]
The processing aid is not particularly limited as long as it is a processing aid generally used in the production of a vinyl chloride resin molded article. For example, an alkyl acrylate-alkyl methacrylate having a weight average molecular weight of 30,000 to 5,000,000 is used. Acrylic processing aids such as copolymers, alkyl acrylate-alkyl methacrylate-styrene copolymers, and the like, specific examples of which include n-butyl acrylate-methyl methacrylate copolymer, 2-ethylhexyl acrylate-methyl methacrylate-butyl And methacrylate copolymers. These may be used alone or in combination of two or more.
[0052]
Examples of the lubricant include an internal lubricant and an external lubricant.
The internal lubricant is used for the purpose of lowering the flow viscosity of the molten resin at the time of molding and preventing frictional heat generation. The internal lubricant is not particularly limited as long as it is an internal lubricant generally used in the production of a vinyl chloride resin molded article.Examples include butyl stearate, lauryl alcohol, stearyl stearate, epoxidized soybean oil, Glycerin monostearate, stearic acid, bisamide and the like can be mentioned. These may be used alone or in combination of two or more.
[0053]
The external lubricant is used for the purpose of enhancing the sliding effect between the molten resin and the metal surface during molding. The external lubricant is not particularly limited as long as it is an external lubricant generally used in the production of a vinyl chloride resin molded article, and examples thereof include montanic acid wax, paraffin wax, polyolefin wax, and ester wax. . These may be used alone or in combination of two or more.
[0054]
The antioxidant is not particularly limited as long as it is an antioxidant generally used in the production of a vinyl chloride-based resin molded product. Examples thereof include a phenolic antioxidant, a sulfur-based antioxidant, and a phosphite. Antioxidants and the like. These may be used alone or in combination of two or more.
[0055]
The light stabilizer is not particularly limited as long as it is a light stabilizer generally used in the production of a vinyl chloride resin molded article, and examples thereof include hindered amine light stabilizers. These may be used alone or in combination of two or more.
[0056]
The ultraviolet absorber is not particularly limited as long as it is an ultraviolet absorber generally used in the production of a vinyl chloride resin molded article. Examples thereof include salicylic acid ester, benzophenone, benzotriazole, and cyanoacrylate. And the like. These may be used alone or in combination of two or more.
[0057]
The antistatic agent is not particularly limited as long as it is an antistatic agent generally used in the production of a vinyl chloride resin molded article. Examples thereof include a cationic antistatic agent and a nonionic antistatic agent. No. These may be used alone or in combination of two or more.
[0058]
The pigment is not particularly limited as long as it is a pigment generally used in the production of a vinyl chloride resin molded article, and examples thereof include organic pigments such as azo-based, phthalocyanine-based, sulene-based and dye lake-based pigments, and oxidized pigments. Pigments, molybdenum chromate-based, sulfide / selenide-based, ferrocyanide-based inorganic pigments, and the like. These may be used alone or in combination of two or more.
[0059]
The filler is not particularly limited as long as it is a filler generally used in the production of a vinyl chloride-based resin molded product.Examples include calcium carbonate, magnesium carbonate, aluminum oxide, magnesium oxide, titanium oxide, and water. Examples include magnesium oxide, talc, mica, clay, and fly ash. These may be used alone or in combination of two or more.
[0060]
The plasticizer is not particularly limited as long as it is a filler generally used in the production of a vinyl chloride-based resin molded article. Examples of the plasticizer include dibutyl phthalate, di-2-ethylhexyl phthalate, and di-2-ethylhexyl adipate. And the like. These may be used alone or in combination of two or more.
[0061]
The method of mixing the organic mercapto-based liquid stabilizer, dialkyltin maleate polymer and various compounding agents with the chlorinated vinyl chloride-based resin is not particularly limited, and may be, for example, mixed with a Henschel mixer, a spar mixer, a ribbon blender, or the like. The mixing may be performed by a hot blend method or a cold blend method. However, when a liquid heat stabilizer, a plasticizer, a lubricant or the like is added, the hot blend method is preferable.
[0062]
As a method for producing a molded article from the chlorinated vinyl chloride resin composition of the present invention, any conventionally known method may be adopted, for example, a single-screw extruder, a bidirectional twin-screw extruder, a conical twin-screw extruder. Extrusion with an extruder such as a press, a press molding method, an injection molding method, and the like.
[0063]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the effects of the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples.
[0064]
(Examples 1 to 8, Comparative Examples 1 to 4)
Synthesis of chlorinated vinyl chloride resin (1) In a glass-lined reactor, 200 parts by weight of deionized water and a vinyl chloride resin produced by a suspension polymerization method (average degree of polymerization: 600, average particle diameter: 150 μm) 40 parts by weight were supplied, and the temperature was raised to 60 ° C. while stirring.
[0065]
Next, after the inside of the reactor was evacuated to remove oxygen, chlorine gas was introduced so that the partial pressure of chlorine became 0.2 MPa, and irradiation with ultraviolet rays started the chlorination reaction. During the chlorination reaction, the reaction temperature was maintained at 60 ° C., and the chlorine partial pressure was maintained at 0.2 MPa. When the chlorine content of the chlorinated vinyl chloride resin reached 65.0% by weight, the supply of chlorine gas and the irradiation of ultraviolet rays were stopped. The chlorination reaction was terminated.
[0066]
After completion of the reaction, nitrogen gas was supplied to remove unreacted chlorine gas, and the obtained slurry was washed with water, dehydrated and dried to obtain a powdery chlorinated vinyl chloride resin (1).
[0067]
Synthesis of chlorinated vinyl chloride resin (2) In a glass-lined reactor, 200 parts by weight of deionized water and a vinyl chloride resin produced by a suspension polymerization method (average degree of polymerization: 600, average particle diameter: 150 μm) 40 parts by weight were supplied, and the temperature was raised to 70 ° C. while stirring.
[0068]
Next, after the inside of the reactor was evacuated to remove oxygen, chlorine gas was introduced so that the chlorine partial pressure became 0.5 MPa, and further heated and heated to 110 ° C. to perform a chlorination reaction.
[0069]
Hydrogen peroxide was added to the vinyl chloride resin at a rate of 5 ppm / hr from the time when the chlorine partial pressure reached 0.5 MPa to one hour before the chlorine content of the chlorinated vinyl chloride resin reached 65.0% by weight. It was added continuously.
[0070]
During the chlorination reaction, the reaction temperature was kept at 110 ° C. and the chlorine partial pressure was kept at 0.5 MPa. When the chlorine content of the chlorinated vinyl chloride resin reached 65.0% by weight, the supply of chlorine gas was stopped and cooling was performed. To terminate the chlorination reaction.
[0071]
After the reaction was completed, nitrogen gas was supplied to remove unreacted chlorine gas, and the obtained slurry was washed with water, dehydrated and dried to obtain a powdery chlorinated vinyl chloride resin (2).
[0072]
Preparation of oily substance (c) 1 mol of di-n-octyltin bis (isooctylmercaptoacetate) and 1 mol of hydrochloric acid were supplied to a flask equipped with a condenser and heated at 150 ° C for 60 minutes. After completion of the heating, the mixture was cooled, and the upper oily substance was separated and washed with water to obtain an oily substance (c).
[0073]
Preparation of organic mercapto-based liquid stabilizer A predetermined amount of the oily substance (c) shown in Table 1 and dibutyltin bis (isooctylmercaptoacetate), dibutyltinbis (stearylmercaptoacetate), stearyl mercaptoacetate and An organic mercapto-based liquid stabilizer was obtained by mixing mercaptoacetic acid isooctyl ester.
[0074]
Preparation of chlorinated vinyl chloride resin molded plate Predetermined amounts of chlorinated vinyl chloride resins (1) and (2), organic mercapto liquid stabilizer, dibutyltin malate polymer, and MBS resin shown in Table 2 5 parts by weight (trade name “C-150S” manufactured by Mitsubishi Rayon Co., Ltd.) and 1 part by weight of lubricant (trade name “G60” manufactured by Cognis Japan Co., Ltd.) are supplied to an 8-inch roll and kneaded at 190 ° C. for 3 minutes. A roll sheet was obtained.
[0075]
After the obtained roll sheet was preheated at 190 ° C. for 3 minutes, it was pressed at 190 ° C. for 4 minutes at a surface pressure of 75 kg / cm ² and cooled to obtain a 2 mm-thick chlorinated vinyl chloride resin molded plate. Obtained.
[0076]
Physical property evaluation of chlorinated vinyl chloride-based resin molded plate The following physical properties were measured for the vinyl chloride-based resin molded plate and the roll sheet obtained above, and the results are shown in Table 2.
[0077]
(1) Thermal Stability A roll sheet obtained by kneading with an 8-inch roll was allowed to stand in a gear oven at 190 ° C., and the time (minute) until blackening was measured.
(2) Yellowness The obtained 2 mm thick chlorinated vinyl chloride resin molded plate was JIS
It was measured according to K7105.
[0078]
(3) Total light transmittance The obtained chlorinated vinyl chloride resin molded plate having a thickness of 2 mm was measured according to JIS K7361-1.
[0079]
[Table 1]

[0080]
[Table 2]

[0081]
【The invention's effect】
As described above, the composition of the chlorinated vinyl chloride resin composition of the present invention is such that (a) dialkyltin bis (mercapto fatty acid ester) represented by the general formula (1) is added to 100 parts by weight of the chlorinated vinyl chloride resin. Hydrochloric acid is added to 5 to 50% by weight, (b) 10 to 50% by weight of a mercapto fatty acid ester represented by the general formula (2) and (c) dialkyltin bis (mercapto fatty acid ester) represented by the general formula (1). In addition, 1 to 7 parts by weight of an organic mercapto-based liquid stabilizer comprising 30 to 75% by weight of an oily substance separated from the obtained product by heating and a dialkyltin malate polymer represented by the general formula (3) Since 0.1 to 2 parts by weight is added, the composition has excellent thermal stability, can be easily thermoformed, and has excellent initial coloring properties.
[0082]
Therefore, the molded article obtained from the chlorinated vinyl chloride resin composition of the present invention is excellent in transparency and flame retardancy, and has mechanical strength and chemical resistance which are advantages of the original chlorinated vinyl chloride resin. Since it also has secondary workability and the like, it can be suitably used as an electronic component case, a food container and the like.
[0083]
Further, when the chlorinated vinyl chloride resin is used as the chlorinated vinyl chloride resin without irradiating the vinyl chloride resin with light, and the chlorinated vinyl chloride resin thermally chlorinated at 60 to 140 ° C. is used, the initial coloring property and the thermal stability are more excellent. As a result, a molded article having more excellent transparency can be obtained.

Claims (2)

100 parts by weight of a chlorinated vinyl chloride resin,
(A) 5 to 50% by weight of a dialkyltin bis (mercapto fatty acid ester) represented by the general formula (1),
(B) 10 to 50% by weight of a mercapto fatty acid ester represented by the general formula (2) and (c) dialkyltin bis (mercapto fatty acid ester) represented by the general formula (1) are heated by adding hydrochloric acid thereto, 1 to 7 parts by weight of an organic mercapto-based liquid stabilizer consisting of 30 to 75% by weight of an oily substance separated from the obtained product;
A chlorinated vinyl chloride resin composition comprising 0.1 to 2 parts by weight of a dialkyltin maleate polymer represented by the general formula (3).

(In the formula, R ¹ and R ² represent an alkyl group having 1 to 16 carbon atoms, R ³ and R ⁴ represent an alkyl group having 1 to 18 carbon atoms, and m represents 1 or 2.)

(Wherein, R ⁵ represents an alkyl group having 1 to 18 carbon atoms or an alkoxyalkyl group having 1 to 5 carbon atoms, and n represents 1 or 2)

(Wherein, R ⁶ represents an alkyl group having 1 to 18 carbon atoms, and p represents an integer of 2 to 4) The chlorinated vinyl chloride-based resin is a chlorinated vinyl chloride-based resin obtained by chlorinating a vinyl chloride-based resin at 60 to 140 ° C. without irradiating the vinyl chloride-based resin with light. A chlorinated vinyl chloride resin composition.