JP2004237683A

JP2004237683A - Method for separating and recovering polymeric material of laminate

Info

Publication number: JP2004237683A
Application number: JP2003031907A
Authority: JP
Inventors: Koji Senda; 弘二仙田; Yasuo Yamamoto; 康雄山本
Original assignee: Sumitomo Riko Co Ltd
Current assignee: Sumitomo Riko Co Ltd
Priority date: 2003-02-10
Filing date: 2003-02-10
Publication date: 2004-08-26

Abstract

<P>PROBLEM TO BE SOLVED: To recover, in a pure state and at a high rate, a material of which the separation and recovery are desirable for the reason of the price or disposal in particular, among polymeric materials constituting a laminate. <P>SOLUTION: The laminate formed by joining a polymeric material layer constituted of a polymeric material A1 showing a small specific gravity α1 and a polymeric material layer constituted of a polymeric material A2 showing a large specific gravity α2 is crushed into minute grains and the crushed grains are suspended in a separating liquid showing an intermediate specific gravity between α1 and α2. A1 grains are separated to be at the liquid level of the separating liquid, A2 grains at the bottom of the liquid and joined grains of A1 and A2 at an intermediate region between the liquid level and the bottom of the liquid, in horizontal distributions respectively, and recovered. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は積層体高分子材料の分離回収方法に関し、更に詳しくは、比重が異なる複数種の高分子材料（例えば、ゴム材料）からなる複数の材料層を持つ積層体において、特に好ましくは各材料層が例えば加硫接着等により強固に結合している場合や回収したい材料層が非常に薄く形成されている場合等において、各材料層を剥離させることなく、しかも各材料層の構成材料を高い収率で分離・回収する積層体高分子材料の分離回収方法に関する。
【０００２】
【従来の技術】
複数の高分子材料層からなる積層体、例えば自動車用ホース等の各種の積層構造ホースや積層構造チューブについても、近年、エネルギーの回収としてのサーマルリサイクルも含めて、高効率で環境負荷の少ないリサイクルが重要視されて来ている。
【０００３】
高分子材料のリサイクルの内、燃料としての利用を考えるサーマルリサイクルは技術面での障害が比較的少ないが、例えばリサイクルに供する積層体がフッ素系等のハロゲン系材料を含む場合、焼却設備を腐食させたり環境を害したりする燃焼ガスを発生するし、ハロゲン系材料は燃料としての熱効率も余り高くない。従って、フッ素ゴム等の高価な高分子材料においては特に材料リサイクルが好ましく、一般的な高分子材料のリサイクルにおいても材料自体を回収して再利用する材料リサイクルが好ましい場合が多い。
【０００４】
【特許文献１】特開昭５９−２１７７３４号公報
【特許文献２】特開平８−１６９９７９号公報
【特許文献３】特開平９−３１２３７号公報
上記の特許文献１に係る「フッ素ゴム再生方法」の発明、特許文献２に係る「加硫フッ素ゴムの再生方法」の発明、特許文献３に係る「架橋した加硫フッ素ゴムの再生方法」の発明には、廃棄処分やサーマルリサイクルに供することなく分離・回収した加硫フッ素ゴムを再生する（例えば、未加硫状態に戻す）ための再生方法が提案されている。
【０００５】
【発明が解決しようとする課題】
ところが、自動車用ホース等の積層体に用いる高分子材料の場合、再利用の前提条件として、積層体を構成する他の高分子材料からピュアな状態で分離する必要がある。しかし、ゴム材料層は他の材料層と強固に加硫接着されている場合が多く、ゴム材料層の界面に沿って剥離することが困難であるため、このようなピュアな状態での分離・回収が容易ではない。
【０００６】
一般的に、カッターにより積層体を界面に沿ってスライスする技術もあるが、正確に界面に沿ってスライスすることは困難で隣接材料層の構成材料が幾分混じり勝ちであるため、必ずしも好適とは言えない。更に、高価なフッ素ゴム等を積層体に用いる場合にはフッ素ゴム層を非常に薄く形成するのが普通であり、その界面に沿ったスライスは一層困難である。
【０００７】
以上の種々の事情から、自動車用ホース等の積層体を構成するフッ素ゴムは、実際には分離・回収されずに、主として埋め立て処分等に供されているのが実情である。そこで本発明は、積層体を構成する高分子材料をピュアな状態で高収率に回収する簡易な方法を提供すること、とりわけ、フッ素ゴムのように価格上又は廃棄処理上の理由から分離・回収が望まれる材料に対して好ましく適用できる方法を提供することを、解決すべき課題とする。
【０００８】
【課題を解決するための手段】
（第１発明の構成）
上記課題を解決するための本願第１発明（請求項１に記載の発明）の構成は、相対的に小さな比重α１を示す高分子材料Ａ１からなる高分子材料層と、相対的に大きな比重α２を示す高分子材料Ａ２からなる高分子材料層とが直接に又は補強糸層を介して接合された積層体に対して、次の工程を行う、積層体高分子材料の分離回収方法である。
（１）前記積層体を細かい粒子に粉砕する工程。この工程は、高分子材料Ａ１とＡ２からなる高分子材料層が補強糸層を介して接合された積層体である場合における、補強糸層に由来する糸屑の選別・排除を含む。
（２）粉砕した粒子を、α１＜αＸ＜α２である比重αＸを示す分離液中に懸濁することにより、高分子材料Ａ１からなる粒子を分離液の液面に、高分子材料Ａ２からなる粒子を分離液の底部に、界面粒子（高分子材料Ａ１及びＡ２が接合された状態にある粒子）を分離液の液面と底部の中間部位に、それぞれ水平分布させる工程。
（３）分離液の液面に分布した高分子材料Ａ１からなる粒子分画、及び／又は、分離液の底部に分布した高分子材料Ａ２からなる粒子分画を、他の粒子分画と分離して回収する工程。
【０００９】
（第２発明の構成）
上記課題を解決するための本願第２発明（請求項２に記載の発明）の構成は、前記第１発明に係る高分子材料Ａ１及び高分子材料Ａ２の少なくとも一方がゴム材料であり、かつ他の高分子材料層に対して加硫接着されている、積層体高分子材料の分離回収方法である。
【００１０】
（第３発明の構成）
上記課題を解決するための本願第３発明（請求項３に記載の発明）の構成は、前記第１発明又は第２発明に係る高分子材料Ａ１及び高分子材料Ａ２の少なくとも一方が価格上又は廃棄処理上の理由から分離・回収が望まれる材料であり、かつその材料層が１．０ｍｍ以下の厚さに形成されている、積層体高分子材料の分離回収方法である。
【００１１】
（第４発明の構成）
上記課題を解決するための本願第４発明（請求項４に記載の発明）の構成は、前記第１発明〜第３発明のいずれかに係る積層体が流体輸送用のホース又はチューブである、積層体高分子材料の分離回収方法である。
【００１２】
（第５発明の構成）
上記課題を解決するための本願第５発明（請求項５に記載の発明）の構成は、前記第１発明〜第４発明のいずれかに係る（１）の工程に関して、次の（４）〜（６）のいずれか１以上の条件を満たす、積層体高分子材料の分離回収方法である。
（４）前記（１）の工程を積層体の冷凍粉砕によって行う。
（５）前記（１）の工程を粗粉砕から微粉砕に到る複数段階で行う。
（６）前記（１）の工程において粉砕した粒子の分級と必要な再粉砕を行う。
【００１３】
（第６発明の構成）
上記課題を解決するための本願第６発明（請求項６に記載の発明）の構成は、任意の比重β１，・・・βｎをそれぞれ示す高分子材料Ｂ１，・・・Ｂｎからそれぞれなる２層以上の高分子材料層が任意の順序で直接に又は補強糸層を介して接合された積層体に対して、次の工程を行うことにより回収を希望する比重βｘの高分子材料Ｂｘからなる粒子を分離して回収する、積層体高分子材料の分離回収方法である。
（１）前記積層体を細かい粒子に粉砕する工程。この工程は、積層体が前記補強糸層を含む場合における、補強糸層に由来する糸屑の選別・排除を含む。
（２）以下の▲１▼〜▲３▼のいずれかの方法により、粉砕した粒子を所定の比重を示す分離液中に懸濁させ、比重βｘの高分子材料Ｂｘからなる粒子を他の粒子分画からと分離させる工程。
▲１▼高分子材料Ｂｘの比重βｘが高分子材料Ｂ１，・・・Ｂｎ中で最小の比重である場合には、この比重βｘより大きく他の高分子材料Ｂ１，・・・Ｂｎの比重より小さな比重を示す分離液を用い、高分子材料Ｂｘからなる粒子のみを分離液の液面に水平分布させる。
▲２▼高分子材料Ｂｘの比重βｘが高分子材料Ｂ１，・・・Ｂｎ中で最大の比重である場合には、この比重βｘより小さく他の高分子材料Ｂ１，・・・Ｂｎの比重より大きな比重を示す分離液を用い、高分子材料Ｂｘからなる粒子のみを分離液の底部に水平分布させる。
▲３▼高分子材料Ｂｘの比重βｘが高分子材料Ｂ１，・・・Ｂｎ中で任意の中間値である場合には、この比重βｘと正確に同一の比重を示す分離液を用い、高分子材料Ｂｘからなる粒子のみを分離液の液面と底部の中間部位に水平分布させる。
（３）上記比重βｘの高分子材料Ｂｘからなる粒子分画を回収する工程。
【００１４】
以上の第６発明において、▲１▼〜▲３▼で「高分子材料Ｂｘからなる粒子のみ」とは、高分子材料Ｂｘのみからなる粒子を言い、高分子材料Ｂｘと他の高分子材料とが接合された界面粒子を含まない概念である。
【００１５】
又、以上の第６発明に関しても、前記の第２発明〜第５発明と同様の実施態様を、第２発明〜第５発明と同様の作用・効果を伴って構成することができる。
【００１６】
（第７発明の構成）
上記課題を解決するための本願第７発明（請求項７に記載の発明）の構成は、順次大きくなる比重γ１，・・・γｎをそれぞれ示す高分子材料Ｃ１，・・・Ｃｎからそれぞれなる２層以上の高分子材料層が任意の順序で直接に又は補強糸層を介して接合された積層体に対して、次の工程を行う、積層体高分子材料の分離回収方法である。
（１）前記積層体を細かい粒子に粉砕する工程。この工程は、積層体が前記補強糸層を含む場合における、補強糸層に由来する糸屑の選別・排除を含む。
（２）粉砕した粒子を、γ１とγｎの中間の比重を示す分離液中に懸濁することにより、該分離液の液面に水平分布する相対的に低比重の粒子分画と、該分離液の底部に水平分布する相対的に高比重の粒子分画と、該分離液の液面と底部の中間部位に水平分布する中間比重の粒子分画とを分離して回収する工程。
（３）上記（２）により回収した粒子分画の内、高分子材料Ｃ１，・・・Ｃｎのいずれかの材料からなる粒子又は界面粒子（いずれか２種の高分子材料が接合された状態にある粒子）が２種以上含まれる粒子分画について、これらの２種以上の粒子の中間の比重を示す分離液中に懸濁して行う上記（２）と同様の粒子分画の比重選別を、高分子材料Ｃ１，・・・Ｃｎのいずれかからなる粒子のみが含まれる粒子分画が得られるまで繰り返し、高分子材料Ｃ１，・・・Ｃｎのいずれかからなる粒子分画の全てを、あるいはその内の回収を希望する粒子分画のみを、分離して回収する工程。
【００１７】
上記の第７発明において、「高分子材料Ｃ１，・・・Ｃｎのいずれかからなる粒子分画」とは、高分子材料Ｃ１，・・・Ｃｎのいずれか１種のみからなる粒子の分画を言い、他種の高分子材料からなる粒子や、高分子材料Ｃ１，・・・Ｃｎのいずれか２種が接合した粒子を含まない概念である。
【００１８】
又、以上の第７発明に関しても、前記の第２発明〜第５発明と同様の実施態様を、第２発明〜第５発明と同様の作用・効果を伴って構成することができる。
【００１９】
（第８発明の構成）
上記課題を解決するための本願第８発明（請求項８に記載の発明）の構成は、順次大きくなる比重δ１，・・・δｎをそれぞれ示す高分子材料Ｄ１，・・・Ｄｎからそれぞれなる２層以上の高分子材料層が任意の順序で直接に又は補強糸層を介して接合された積層体に対して、次の工程を行うことを特徴とする積層体高分子材料の分離回収方法。
（１）前記積層体を細かい粒子に粉砕する工程。この工程は、積層体が前記補強糸層を含む場合における、補強糸層に由来する糸屑の選別・排除を含む。
（２）粉砕した粒子を、互いに相溶しない複数種の分離液であってそれぞれδ１＜δＸ＜δ２である比重δＸを持つ分離液、δ２＜δＹ＜δ３である比重δＹを持つ分離液、・・・が層状に階層分離した複合分離液中に懸濁することにより、高分子材料Ｄ１，・・・Ｄｎのいずれかからなる粒子を複合分離液の液面、複合分離液の底部、又は各分離液の界面に水平分布させると共に、界面粒子（高分子材料Ｄ１，・・・Ｄｎの内の２種の高分子材料が接合された状態にある粒子）を各分離液の階層内に水平分布させる工程。
（３）複合分離液の液面、複合分離液の底部、又は各分離液の界面に水平分布した高分子材料Ｄ１，・・・Ｄｎのいずれかからなる粒子分画の内、回収を希望する粒子分画を他の粒子と分離して回収する工程。
【００２０】
上記の第８発明において、「高分子材料Ｄ１，・・・Ｄｎのいずれかからなる粒子分画」とは、高分子材料Ｄ１，・・・Ｄｎのいずれか１種のみからなる粒子の分画を言い、他種の高分子材料からなる粒子や、高分子材料Ｄ１，・・・Ｄｎのいずれか２種が接合した界面粒子を含まない概念である。
【００２１】
又、以上の第８発明に関しても、前記の第２発明〜第５発明と同様の実施態様を、第２発明〜第５発明と同様の作用・効果を伴って構成することができる。
【００２２】
【発明の作用・効果】
（第１発明の作用・効果）
第１発明においては、高分子材料Ａ１からなる高分子材料層と高分子材料Ａ２からなる高分子材料層とが接合された積層体を細かい粒子に粉砕し、その際には必要に応じて補強糸層に由来する糸屑の選別・排除を行い、粒子を所定の比重を示す分離液中に懸濁させて、高分子材料Ａ１からなる粒子と、高分子材料Ａ２からなる粒子と、両者の材料からなる界面粒子とを、分離液中の互いに分離された部位にピュアな状態で水平分布させるので、それぞれの粒子分画を適当な手段によって容易に分離・回収できる。
【００２３】
従って粉砕と比重選別と言う簡易で低コストな方法により、Ａ１材料とＡ２材料の大部分を（即ち、界面粒子の粒子分画を除いて）ピュアな状態で容易に分離・回収できる。そしてＡ１材料層とＡ２材料層が強固に加硫接着されている場合にも支障なく実施できるし、Ａ１材料層及び又はＡ２材料層が薄く形成されていても、粉砕の粒度をそれに対応して細かくすることにより、薄く形成された材料層の大部分をピュアな状態で容易に分離・回収できる。
【００２４】
なお、粒子の比重選別方法としては、他にもサイクロン等を利用する気体（空気）を分離媒体とする選別方法が知られている。しかし、この場合、互いの比重差が余り大きくない高分子材料粒子間では、高い分離効率を期待し難い。又、粒子の比重以外の要素（粒径や粒子形状）の影響が大きく、高分子材料粒子をピュアな状態で分離・回収することは困難である。
【００２５】
こうして第１発明により分離・回収されたＡ１材料及び又はＡ２材料は、例えば、そのままで、あるいは一定の材質劣化回復処理を経て、あるいはゴム材料である場合には未加硫状態に戻す再生処理を経て、再度成形材料としての利用に供することができる。又、回収された粒子の形態のままで、例えば充填材としての利用に供することもできる。もち論、サーマルリサイクルに供することも可能である。
【００２６】
（第２発明の作用・効果）
上記の第１発明に係る積層体高分子材料の分離回収方法は、前記した理由から、高分子材料Ａ１及び／又は高分子材料Ａ２がゴム材料であり、かつその材料層が他の高分子材料層に対して加硫接着されている場合において、特に好ましく適用される。
【００２７】
（第３発明の作用・効果）
上記の第１発明に係る積層体高分子材料の分離回収方法は、前記した理由から、高分子材料Ａ１及び／又は高分子材料Ａ２が価格上又は廃棄処理上の理由で分離・回収が望まれる材料である場合に特に好ましく適用され、とりわけ、その材料層が１．０ｍｍ以下の厚さに形成されている場合に好ましく適用される。
【００２８】
（第４発明の作用・効果）
積層体高分子材料の分離回収方法の対象となる積層体の好ましい一例として、流体輸送用のホース又はチューブを挙げることができる。
【００２９】
（第５発明の作用・効果）
上記の第１発明で述べた、（１）積層体を細かい粒子に粉砕する工程に関して、粉砕手段としては積層体の冷凍粉砕が特に好ましく、又、適宜な手段を用いて粉砕を粗粉砕から微粉砕に到る２段階以上の複数段階で行うことも特に好ましく、更に、粉砕した粒子を振動篩等で分級して選別することも特に好ましい。分級された過大な粒子は、再度の粉砕処理に供することができる。第１発明において前記した補強糸層に由来する糸屑の選別・排除は、好ましくはこの分級選別の際に行うことができる。
【００３０】
（第６発明の作用・効果）
第６発明においては、積層体が２層の高分子材料層からなる場合には第１発明と同様の効果が得られる他、積層体が３層以上の高分子材料層からなる場合においても、２種以上の材料が接合した界面粒子を排除しつつ、各高分子材料層を構成する高分子材料Ｂ１，・・・Ｂｎのそれぞれについてピュアな状態で容易に分離・回収できる。
【００３１】
（第７発明の作用・効果）
第７発明においては、積層体が２層の高分子材料層からなる場合には第１発明と同様の効果が得られる他、積層体が３層以上の高分子材料層からなる場合においても、２種以上の材料が接合した界面粒子を排除しつつ、各高分子材料層を構成する高分子材料Ｂ１，・・・Ｂｎのそれぞれについてピュアな状態で容易に分離・回収できる。
【００３２】
同様な効果を期待できる上記の第６発明と比較すると、分離液の構成及び各粒子分画の分離・回収工程がやや複雑化するものの、多数の高分子材料層を構成する高分子材料Ｂ１，・・・Ｂｎの粒子を、分離液による一度の比重選別によって分離・回収できると言う利点がある。
【００３３】
（第８発明の作用・効果）
第８発明においては、２層〜多数層の高分子材料層が任意の順序で積層体において、その内の特定の高分子材料層の材料だけをピュアな状態で分離・回収したい場合において、分離液の構成及び各粒子分画の分離・回収工程を複雑化させることなく、分離液による一度の比重選別によって分離・回収できると言う利点がある。
【００３４】
【発明の実施の形態】
次に、第１発明〜第８発明の実施の形態について説明する。以下において単に「本発明」と言うときは第１発明〜第８発明を一括して指している。
【００３５】
〔第１発明〜第８発明に共通する実施の形態〕
（積層体及び高分子材料）
本発明に係る積層体は、高分子材料層が直接に又は補強糸層を介して接合された積層体であって、少なくとも分離・回収したい高分子材料の比重が他の高分子材料とは異なるものである。積層体の好ましい実施形態として、前記第１発明のような、相対的に小さな比重α１を示す高分子材料Ａ１からなる高分子材料層と、相対的に大きな比重α２を示す高分子材料Ａ２からなる高分子材料層とが接合された積層体を例示することができる。
【００３６】
積層体の他の好ましい実施形態として、前記第６発明のように任意の比重β１，β２，・・・βｎをそれぞれ示す高分子材料Ｂ１，Ｂ２，・・・Ｂｎからそれぞれなる２層以上の高分子材料層が任意の順序で直接に又は補強糸層を介して接合された積層体も例示できる。更に、前記第７発明や第８発明のように順次大きくなる比重γ１，γ２，・・・γｎ（δ１，δ２，・・・δｎ）をそれぞれ示す高分子材料Ｃ１，Ｃ２，・・・Ｃｎ（Ｄ１，Ｄ２，・・・Ｄｎ）からそれぞれなる２層以上の高分子材料層が任意の順序で直接に又は補強糸層を介して接合された積層体も例示できる。
【００３７】
高分子材料は、種々に異なる比重を示す。特に、多種の充填剤が配合されるゴム材料においては、同一のポリマーを用いた場合にも、その配合内容により比重は異なる。実用的に用いられているゴム材料の比重として、例えば、フッ素ゴム（ＦＫＭ）の比重は約１．８〜１．９、エピクロルヒドリンゴム（ＥＣＯ）やシリコーンゴム（Ｑ）やクロロプレンゴム（ＣＲ）等の比重は約１．４〜１．６、アクリロニトリル−ブタジエンゴム（ＮＢＲ）やアクリル系ゴム（ＡＣＭ，ＡＥＭ）やエチレンプロピレンゴム（ＥＰＤＭ）等の比重は約１．１〜１．３を示す。又、樹脂材料の例としては、例えばポリアミド樹脂の比重は約１．０〜１．２、ガラス繊維補強されたポリアミド樹脂の比重は約１．３〜１．５を示す。更に、フッ素系樹脂については、材料種によって大きく異なり、その比重は約１．７〜２．２と言う範囲にある。従って、殆どの高分子材料積層体において、本発明の適用が可能な材料間の比重関係を見出すことができる。
【００３８】
これらの積層体において、高分子材料層間の接合の形態は限定されない。即ち、単に高分子材料の粘着性等により接合状態が維持されたり、通常の接着剤により接合されたりしている場合のように、比較的容易に界面に沿って剥離できる状態の接合形態も含まれるし、ゴム層−ゴム層間あるいはゴム層−樹脂層間で加硫接着されている場合のように、界面に沿って剥離することが困難である状態の接合形態も含まれる。後者の場合の方が、本発明を適用することによるメリットが大きい。
【００３９】
このような接合の形態において、高分子材料層間が直接に接合されている場合もあるし、例えば補強糸層や接着剤層等のような界面層を介在させて接合されている場合もある。高分子材料層間が補強糸層を介在させて接合されている場合には、後述のように、積層体を粉砕した後に、補強糸層に由来する糸屑を排除できる分級処理を行うことが好ましい。
【００４０】
積層体の種類は限定されないが、例えばゴム材料層及び／又は樹脂材料層が積層された流体輸送用のホース又はチューブ、特に自動車用のホース又はチューブが好ましく例示される。これらの積層体において、高分子材料層間に補強糸層が介在するものも、前記のように本発明の対象となる。又、高分子材料層間に金属薄膜層を含むものも、本発明の対象となり得る。この場合、金属薄膜層は積層体の粉砕後に分級選別により排除できるし、それが困難な場合にも、金属薄膜層を含む粒子を界面粒子として特有の比重に従って分離液中で分離可能である。更に、高分子材料層間にワイヤーブレード層等の粉砕困難な構成要素を含むものも、それらの構成要素を予め剥離・除外することが可能であれば、本発明の対象となり得る。
【００４１】
積層体の高分子材料層の厚さや、高分子材料層を構成する高分子材料の種類は限定されない。高分子材料層の厚さに関しては、１．０ｍｍ以下の厚さに形成された高分子材料層を含み、かつその高分子材料層の構成材料を分離・回収したい場合に、本発明を適用することによるメリットが大きい。高分子材料層を構成する高分子材料に関しては、任意の種類のゴム材料、樹脂材料、エラストマー材料が含まれるが、本発明を適用することによるメリットが特に大きい高分子材料として、以下の第１〜第３の材料が例示される。
第１の材料：任意の粒径への粉砕が容易な材料、例えばゴム材料や樹脂材料。
第２の材料：価格上の理由から分離・回収が望まれる材料。例えばフッ素ゴム、フルオロシリコーンゴム、フッ素系樹脂。
第３の材料：廃棄処理上の理由から分離・回収が望まれる材料。例えばサーマルリサイクルに不向きな塩素、フッ素等のハロゲン系元素を高濃度で含むゴム材料又は樹脂材料。それらの例示としてのクロロプレンゴム、エピクロルヒドリンゴム、フッ素ゴム、各種フッ素系の樹脂。
【００４２】
（積層体の粉砕工程）
積層体は、まず細かい粒子に粉砕される。粉砕の方法及び手段は限定されず、例えば一度の粉砕で済ませることもできるし、粗粉砕から微粉砕に到る２段階以上の複数段階で行うこともできる。積層体を冷凍粉砕することもできる。好ましい粉砕形態の一例として、積層体を冷凍状態でクラッシャーやグラインダーにより粗粉砕及び微粉砕することができる。粉砕の過程において、篩や振動篩等によって分級選別して、過大な粒子分画は再度の粉砕に供することもできる。積層体が補強糸層を含むものである場合、この分級選別の過程で補強糸層に由来する糸屑を排除できる。
【００４３】
積層体の粉砕により、いずれかの高分子材料層の構成材料のみからなる粒子と、積層体の層間の界面部分を構成していた界面粒子（異なる高分子材料層の構成材料が接合した状態の粒子）とが生成する。通常は界面粒子は回収の対象とはならないため、この観点からは界面粒子の総重量を小さくするような（即ち、より小さな粒径への）粉砕が好ましい。反面、余りに小さな粒径への粉砕は、効率やコストの面で有利ではなく、かつ一般的に分離液中での迅速な比重選別が困難になり易い。
【００４４】
上記の事情を考慮して粉砕の程度は任意に決定すれば良いが、一般的には、積層体を構成する最も薄い高分子材料層の厚さ、あるいは分離・回収したい高分子材料層の厚さに対して５分の１〜１０分の１程度の粒径に粉砕することが好ましい。例えば、分離・回収したいフッ素ゴム層が０．５〜０．８ｍｍ程度の薄い層である場合には、１００〜１５０μｍの粒度に粉砕することが好ましい。本発明の方法によれば、前記のサイクロン等を利用する方法に比較して、粒子分画の分離に対する粒径の影響は少ないが、粒径がある程度の狭い範囲に分布するに越したことはない。
【００４５】
（粉砕粒子の分離・回収工程）
粉砕した粒子は、分離槽中に収容させた所定の比重を持つ分離液中に懸濁することにより、それぞれの高分子材料層の構成材料のみからなる粒子や界面粒子を、それぞれ分離液中の異なる高さ部位に水平分布させる。粉砕した粒子を分離液中に懸濁させるに当たり、粉砕粒子に対する気泡の付着等を防止するため、攪拌したり、超音波振動等で加振したりすることも、好ましい。
【００４６】
そして、適当な手段により、希望する粒子分画を分離・回収する。分離槽は、分離液を収容した状態において、その液面部、底部又は中間部位に分布した粒子分画を掬い取ったり抜き取ったりすることが可能な構成を備えていれば良い。例えば、分離槽を任意の高さ部位において水平方向に区画できる複数の開閉可能なシャッターを備えた構造を挙げることができる。
【００４７】
相対的に小さな比重α１を示す高分子材料Ａ１からなる高分子材料層と、相対的に大きな比重α２を示す高分子材料Ａ２からなる高分子材料層とが接合された積層体を粉砕すると、高分子Ａ１からなる粒子（Ａ１粒子）と、高分子材料Ａ２からなる粒子（Ａ２粒子）と、両者の材料が接合した界面粒子（Ａ１／Ａ２粒子）とを生成する。これらの粒子を比重αＸ（α１＜αＸ＜α２）である分離液中に懸濁すれば、Ａ１粒子は分離液の液面に浮上し、Ａ２粒子は分離液の底部に沈降し、Ａ１／Ａ２粒子は液面と底部の中間部位にある程度の拡がりを伴って分布する。従って、適当な手段で液面部のＡ１粒子分画のみを掬い取ったり、底部のＡ２粒子分画のみを抜き取ったりすることは容易である。
【００４８】
分離液としては、各種のいわゆる有機溶媒や無機溶媒を、その固有の比重に着目して、任意に選択して使用できる。これらの溶媒に一定の溶質を溶解させることにより、比重を調整した分離液とすることもできる。例えば、比重が約１．５であるＥＣＯ粒子と、比重が約１．８であるＦＫＭ粒子と、これらの界面粒子とを分離するための分離液としては、比重が１．６１であるヘキサフルオロベンゼン等を好ましく使用できる。
【００４９】
分離液としては、更に、いわゆる超臨界状態のガス（例えば、炭酸ガスその他の不活性ガス）も、好ましく用いることができる。即ち、圧力と温度を調整できる堅牢な容器中に炭酸ガスと高分子材料粒子を充填し、所定の圧力と温度に設定して炭酸ガスの比重を上記のαＸに制御すると、Ａ１粒子、Ａ２粒子及びＡ１／Ａ２粒子を上記と同様に比重選別できる。
【００５０】
〔第６発明〜第８発明の実施の形態〕
第６発明〜第８発明は、積層体が２層の高分子材料層からなる場合に加え、積層体が３層以上の高分子材料層からなる場合にも、回収を希望する高分子材料をピュアな状態で高収率に分離・回収できる。
【００５１】
（第６発明の実施の形態）
第６発明は、２層又は３層以上の高分子材料層からなる積層体において、特定の比重を示す高分子材料のみを回収したい場合に、特に効率の良い方法である。
即ち、任意の比重β１，・・・βｎをそれぞれ示す高分子材料Ｂ１，・・・Ｂｎからそれぞれなる２層以上の高分子材料層が任意の順序で直接に又は補強糸層を介して接合された積層体に対して、第１発明と同様の粉砕工程を行い、その後の分離液を用いる比重選別工程において、以下の▲１▼〜▲３▼のいずれかを行う。
【００５２】
▲１▼高分子材料Ｂｘの比重βｘが高分子材料Ｂ１，・・・Ｂｎ中で最小の比重である場合には、この比重βｘより大きく他の高分子材料Ｂ１，・・・Ｂｎの比重より小さな比重を示す分離液を用い、高分子材料Ｂｘからなる粒子（Ｂｘ粒子）のみを分離液の液面に水平分布させる。高分子材料Ｂｘが含まれた界面粒子も、Ｂｘ粒子よりは比重が大きいから分離液の液面には分布せず、Ｂｘ粒子と分離できる。
【００５３】
▲２▼高分子材料Ｂｘの比重βｘが高分子材料Ｂ１，・・・Ｂｎ中で最大の比重である場合には、この比重βｘより小さく他の高分子材料Ｂ１，・・・Ｂｎの比重より大きな比重を示す分離液を用い、高分子材料Ｂｘからなる粒子（Ｂｘ粒子）のみを分離液の底部に水平分布させる。高分子材料Ｂｘが含まれた界面粒子も、Ｂｘ粒子よりは比重が小さいから分離液の底部には分布せず、Ｂｘ粒子と分離できる。
【００５４】
▲３▼高分子材料Ｂｘの比重βｘが高分子材料Ｂ１，・・・Ｂｎ中で任意の中間値である場合には、この比重βｘと正確に同一の比重を示す分離液を用い、高分子材料Ｂｘからなる粒子（Ｂｘ粒子）のみを分離液の液面と底部の中間部位に水平分布させる。高分子材料Ｂｘが含まれた界面粒子も、Ｂｘ粒子とは比重が一致しないから分離液の液面又は底部に分布し、Ｂｘ粒子と分離できる。
【００５５】
（第７発明の実施の形態）
第７発明は、２層又は３層以上の高分子材料層からなる積層体において、互いに異なる比重を示す２種以上の高分子材料を簡単なデバイスによって分離・回収したい場合に、特に効率の良い方法である。
【００５６】
即ち、順次大きくなる比重γ１，・・・γｎをそれぞれ示す高分子材料Ｃ１，・・・Ｃｎからそれぞれなる２層以上の高分子材料層が任意の順序で直接に又は補強糸層を介して接合された積層体に対して、第１発明と同様の粉砕工程を行い、その後の分離液を用いる比重選別工程において、第１発明と同様の比重選別工程を分離液の比重を選択しつつ複数回繰り返して、各比重別の粒子分画をそれぞれ分離・回収するのである。従って、複数回の比重選別工程において、異なる比重を示す２種以上の分離液を使い分ける必要がある。
【００５７】
但し、前記したような超臨界状態の炭酸ガス等を利用する場合、圧力と温度の設定によって比重を次第に大きくなる方向へ（又は、次第に小さくなる方向へ）連続的に変化させることにより、最も小さな比重を示す高分子材料から順次に（又は、最も小さな比重を示す高分子材料から順次に）、連続的に分離・回収を繰り返すことが可能である。
【００５８】
（第８発明の実施の形態）
第８発明は、２層又は３層以上の高分子材料層からなる積層体において、互いに異なる比重を示す２種以上の高分子材料を一度のプロセスによって分離・回収したい場合に、特に効率の良い方法である。
【００５９】
即ち、順次大きくなる比重δ１，・・・δｎをそれぞれ示す高分子材料Ｄ１，・・・Ｄｎからそれぞれなる２層以上の高分子材料層が任意の順序で直接に又は補強糸層を介して接合された積層体に対して、第１発明と同様の粉砕工程を行い、その後の分離液を用いる比重選別工程において複合分離液を用いる。複合分離液は、互いに異なる比重δＸ，δＹ，・・・（δ１＜δＸ＜δ２、δ２＜δＹ＜δ３、・・・である）を示し相溶しない複数種の分離液が、層状に階層分離したものである。このような複合分離液の構成例として、水と油液との併用、水と有機溶媒と油液との併用、等を例示することができる。
【００６０】
【実施例】
（実施例１）
図１に示す積層体１は，自動車用のゴムホースであって、最内層２が厚さ０．５ｍｍのＦＫＭからなり、その外周側に順次、厚さ１．０ｍｍのＥＣＯからなる中間層３、補強糸層４、厚さ１．５ｍｍのＥＣＯからなる外皮層５を備えている。
【００６１】
この積層体１を図２に示すフローチャートに従って処理した。即ち、最初に粗粉砕工程６において積層体１をクラッシャー等の破砕機を用いて粒径１〜２ｍｍ程度まで、粗粉砕を行った。次に、得られたゴム粒子を冷凍工程７において液体窒素を用いた装置により冷凍した後、微粉砕工程８においてグラインダーを用いて粒径が約１００〜２００μｍとなるよう、微粉砕を行った。その後、粉砕粒子の冷凍状態を解除したもとで、分級工程９において振動篩を用いて粒子を分級し、補強糸層４に由来する糸屑を排除した。又、この分級工程９において、１００メッシュ篩上（約１５０μｍ以上）の粗粒子を一旦回収し、この粗粒子について、工程８を繰り返すと言う付加工程を必要な回数反復実施した。
【００６２】
こうして調製された粒径１００〜１５０μｍの粒子集合体を、分離液分散工程１０で比重選別した。即ち、上記の粒子集合体を、図３に示す分離槽１１に収容した分離液１２中に投入して攪拌し、懸濁させた。この分離槽１１は、図示を省略するが、液面部位の分離液１２を掬い取る手段と、底部の分離液１２を容器底部方向に抜き取る手段とを備えている。又、分離液１２は前記したヘキサフルオロベンゼン（Ｃ_６Ｆ_６）である。
【００６３】
上記の粒子集合体を分離液１２中に懸濁させた後、約１分間静置すると、図３に示すように、分離液１２の液面部位にはＥＣＯからなる粒子１３が、分離液１２の底部にはＦＫＭからなる粒子１４が、分離液１２の中間部位にはＥＣＯとＦＫＭが接合した状態にある界面粒子１５がそれぞれ分布した。
【００６４】
そこで、分離槽１１の底部からＦＫＭ粒子１４の分画を抜き取り、分離槽１１の液面部位からはＥＣＯ粒子１３の分画を掬い取ることにより、積層体１を構成していたＦＫＭとＥＣＯとの大部分を、ピュアな状態で分離して回収することができた。
【００６５】
（実施例２及び比較例）
実施例１と同様のプロセスにより調製した粒子集合体について、分離層１１と同様の機構を備えた堅牢な分離槽を用い、超臨界状態の炭酸ガスを利用して比重選別を行い、積層体１を構成していたＦＫＭとＥＣＯとの大部分を、分離して回収した。
【００６６】
一方、比較例として、実施例１と同様のプロセスにより調製した粒子集合体について、公知のサイクロン方式による選別を試みた。更に実施例１と同一の積層体１について、ホースを軸方向沿いに切り開いて平坦状に強制展開させたもとで、薄いカッターにより積層体を界面に沿ってスライスする分離方法も試みた。
【００６７】
以上の実施例１、実施例２、及び比較例をそれぞれ複数回行った結果による、ＦＫＭとＥＣＯとのそれぞれの回収率の範囲を、下記の表１にまとめて示す。
【００６８】
【表１】

【図面の簡単な説明】
【図１】実施例に係る積層体を示す断面図である。
【図２】実施例１のフローチャートを示す図である。
【図３】実施例１の比重選別工程を簡略化して示す断面図である。
【符号の説明】
１積層体
２最内層
３中間層
４補強糸層
５外皮層
６〜１０工程
１１分離槽
１２分離液
１３，１４粒子
１５界面粒子[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for separating and recovering a laminate polymer material, and more particularly, to a laminate having a plurality of material layers composed of a plurality of types of polymer materials (for example, rubber materials) having different specific gravities, particularly preferably each material layer. For example, when the material layers are firmly bonded by vulcanization bonding or when the material layer to be collected is formed very thin, etc., the material of each material layer can be obtained with high yield without peeling each material layer. The present invention relates to a method for separating and collecting a laminated polymer material separated and recovered at a high rate.
[0002]
[Prior art]
In recent years, with regard to laminates composed of a plurality of polymer material layers, for example, various kinds of laminated hoses and laminated tubes such as automotive hoses, high-efficiency and low environmental impact recycling, including thermal recycling as energy recovery, has recently been conducted. Is gaining importance.
[0003]
Among the recycling of polymer materials, thermal recycling, which considers use as a fuel, has relatively few technical obstacles.However, if the laminate to be recycled contains halogen-based materials such as fluorine, the incineration equipment will be corroded. It generates combustion gases that cause harm to the environment and harms the environment. Halogen-based materials do not have very high thermal efficiency as fuel. Therefore, in the case of expensive polymer materials such as fluororubber, material recycling is particularly preferable. In general, in recycling of general polymer materials, material recycling in which the materials themselves are collected and reused is often preferable.
[0004]
[Patent Document 1] JP-A-59-217734
[Patent Document 2] Japanese Patent Application Laid-Open No. 8-169799
[Patent Document 3] JP-A-9-31237
The invention of the "method of regenerating fluororubber" according to Patent Document 1 described above, the invention of "method of regenerating vulcanized fluororubber" according to Patent Document 2, and the "method of regenerating crosslinked vulcanized fluororubber" according to Patent Document 3 The invention proposes a regeneration method for regenerating (for example, returning to an unvulcanized state) the separated and recovered vulcanized fluoro rubber without being subjected to disposal or thermal recycling.
[0005]
[Problems to be solved by the invention]
However, in the case of a polymer material used for a laminate such as an automobile hose, it is necessary to separate the polymer material from other polymer materials constituting the laminate in a pure state as a precondition for reuse. However, the rubber material layer is often firmly vulcanized and bonded to other material layers, and it is difficult to peel off along the interface of the rubber material layer. Recovery is not easy.
[0006]
In general, there is also a technique of slicing the laminate along the interface with a cutter, but it is difficult to accurately slice along the interface, and the constituent materials of the adjacent material layers tend to be mixed together, so it is not necessarily preferred. I can't say. Further, when expensive fluorine rubber or the like is used for the laminate, the fluorine rubber layer is usually formed very thin, and slicing along the interface is more difficult.
[0007]
From the above various circumstances, the fact is that the fluororubber constituting the laminate, such as a hose for an automobile, is actually used for landfill disposal or the like without being actually separated and collected. Therefore, the present invention provides a simple method of recovering a polymer material constituting a laminate in a pure state with a high yield. An object to be solved is to provide a method which can be preferably applied to a material whose recovery is desired.
[0008]
[Means for Solving the Problems]
(Configuration of the first invention)
In order to solve the above-mentioned problem, the first invention (the invention described in claim 1) comprises a polymer material layer made of a polymer material A1 having a relatively small specific gravity α1 and a relatively large specific gravity α2. This is a method for separating and recovering a laminated polymer material, in which the following steps are performed on a laminate in which a polymer material layer made of a polymer material A2 is bonded directly or via a reinforcing yarn layer.
(1) A step of pulverizing the laminate into fine particles. This step includes selection and elimination of lint originating from the reinforcing yarn layer when the polymer material layer composed of the polymeric materials A1 and A2 is a laminate joined via the reinforcing yarn layer.
(2) The particles made of the polymer material A1 are suspended on the liquid surface of the separated solution by suspending the pulverized particles in a separation solution having a specific gravity αX satisfying α1 <αX <α2. A step of horizontally distributing the particles at the bottom of the separated liquid and the interfacial particles (particles in a state where the polymer materials A1 and A2 are bonded) at an intermediate portion between the liquid surface and the bottom of the separated liquid;
(3) Separating the particle fraction composed of the polymer material A1 distributed on the liquid surface of the separated liquid and / or the particle fraction composed of the polymeric material A2 distributed on the bottom of the separated liquid from other particle fractions And collecting.
[0009]
(Structure of the second invention)
According to a second aspect of the present invention (an invention according to a second aspect) for solving the above-mentioned problem, at least one of the polymer material A1 and the polymer material A2 according to the first invention is a rubber material, and This is a method for separating and recovering a laminated polymer material that is vulcanized and bonded to the polymer material layer of (1).
[0010]
(Structure of the third invention)
According to a third aspect of the present invention (an invention according to claim 3) for solving the above-mentioned problems, at least one of the polymer material A1 and the polymer material A2 according to the first invention or the second invention is expensive or expensive. This is a method for separating and collecting a laminated polymer material, which is a material which is desired to be separated and collected for reasons of disposal, and whose material layer is formed to a thickness of 1.0 mm or less.
[0011]
(Structure of the fourth invention)
According to a fourth aspect of the present invention (an invention described in claim 4) for solving the above-mentioned problems, the laminate according to any one of the first to third aspects is a fluid transport hose or tube. This is a method for separating and recovering a laminated polymer material.
[0012]
(Structure of the fifth invention)
The configuration of the fifth invention of the present application (the invention described in claim 5) for solving the above-mentioned problem is as follows: (1) according to any one of the first invention to the fourth invention, the following (4) to (4). This is a method for separating and recovering a laminated polymer material that satisfies at least one of the conditions (6).
(4) The step (1) is performed by freeze-grinding the laminate.
(5) The step (1) is performed in a plurality of stages from coarse pulverization to fine pulverization.
(6) Classifying the particles pulverized in the step (1) and performing necessary re-pulverization.
[0013]
(Structure of the sixth invention)
In order to solve the above-mentioned problem, the configuration of the sixth invention of the present application (the invention according to claim 6) is a two-layer structure made of polymer materials B1,... Bn each having an arbitrary specific gravity β1,. Particles made of the polymer material Bx having a specific gravity βx desired to be recovered by performing the following steps on the laminate in which the above polymer material layers are bonded directly in any order or via the reinforcing yarn layer This is a method for separating and collecting a laminated polymer material.
(1) A step of pulverizing the laminate into fine particles. This step includes selection and elimination of yarn waste derived from the reinforcing yarn layer when the laminate includes the reinforcing yarn layer.
(2) The pulverized particles are suspended in a separation liquid having a predetermined specific gravity by any of the following methods (1) to (3), and the particles composed of the polymer material Bx having a specific gravity βx are replaced with other particles. Separating from fractionation.
{Circle around (1)} When the specific gravity βx of the polymer material Bx is the smallest specific gravity among the polymer materials B1,... Bn, the specific gravity βx is larger than the specific gravity βx and is smaller than the specific gravity of the other polymer materials B1,. Using a separation liquid having a small specific gravity, only particles composed of the polymer material Bx are horizontally distributed on the liquid surface of the separation liquid.
{Circle around (2)} When the specific gravity βx of the polymer material Bx is the largest specific gravity among the polymer materials B1,... Bn, the specific gravity βx is smaller than the specific gravity βx and is smaller than the specific gravity of the other polymer materials B1,. Using a separation liquid having a large specific gravity, only particles composed of the polymer material Bx are horizontally distributed at the bottom of the separation liquid.
{Circle around (3)} When the specific gravity βx of the polymer material Bx is an arbitrary intermediate value in the polymer materials B1,..., Bn, a separation liquid having exactly the same specific gravity as the specific gravity βx is used. Only the particles composed of the material Bx are horizontally distributed at an intermediate portion between the liquid level and the bottom of the separated liquid.
(3) a step of collecting a particle fraction composed of the polymer material Bx having the above specific gravity βx.
[0014]
In the sixth invention described above, “only the particles made of the polymer material Bx” in (1) to (3) means particles made of only the polymer material Bx, and the polymer material Bx and the other polymer material are combined. Is a concept that does not include bonded interface particles.
[0015]
Also, with regard to the above-described sixth invention, the same embodiments as those of the above-described second to fifth inventions can be configured with the same operations and effects as those of the second to fifth inventions.
[0016]
(Structure of the seventh invention)
The configuration of the seventh invention of the present application (the invention according to claim 7) for solving the above-mentioned problem is that each of the polymer materials C1,..., Cn exhibiting a specific gravity γ1,. This is a method for separating and recovering a laminated polymer material, in which the following steps are performed on a laminate in which at least two polymer material layers are joined in an arbitrary order directly or via a reinforcing yarn layer.
(1) A step of pulverizing the laminate into fine particles. This step includes selection and elimination of yarn waste derived from the reinforcing yarn layer when the laminate includes the reinforcing yarn layer.
(2) By suspending the pulverized particles in a separation liquid having a specific gravity between γ1 and γn, a relatively low-specific-gravity particle fraction horizontally distributed on the liquid surface of the separation liquid is obtained. A step of separating and collecting a relatively high-specific-gravity particle fraction horizontally distributed at the bottom of the liquid and an intermediate-specific-particle fraction horizontally distributed at an intermediate portion between the liquid surface and the bottom of the separated liquid.
(3) Among the particle fractions collected in the above (2), particles or interface particles composed of any one of the polymer materials C1,... Cn (state in which any two kinds of the polymer materials are joined) Of the particles containing two or more kinds of particles in the same manner as the above (2), which is suspended in a separation liquid having an intermediate specific gravity between these two or more kinds of particles. Is repeated until a particle fraction containing only particles composed of any of the polymer materials C1,... Cn is obtained, and all of the particle fractions composed of the polymer materials C1,. Alternatively, a step of separating and collecting only the particle fraction desired to be collected.
[0017]
In the above seventh invention, “fractionation of particles composed of any one of the polymer materials C1,... Cn” means fractionation of particles composed of only one of the polymer materials C1,. This is a concept that does not include particles made of another type of polymer material or particles obtained by joining any two of the polymer materials C1,... Cn.
[0018]
Also, with regard to the seventh invention described above, embodiments similar to the second to fifth inventions described above can be configured with the same operations and effects as the second to fifth inventions.
[0019]
(Configuration of the eighth invention)
In order to solve the above-mentioned problem, the configuration of the eighth invention of the present application (the invention according to claim 8) is that the polymer materials D1,..., Dn exhibiting the specific gravities δ1,. A method for separating and recovering a laminated polymer material, comprising performing the following steps on a laminate in which at least two polymer material layers are joined in any order directly or via a reinforcing yarn layer.
(1) A step of pulverizing the laminate into fine particles. This step includes selection and elimination of yarn waste derived from the reinforcing yarn layer when the laminate includes the reinforcing yarn layer.
(2) Separated liquids having a specific gravity δX satisfying δ1 <δX <δ2, separated liquids having specific gravity δX satisfying δ1 <δX <δ2, respectively, Are suspended in a layered composite separation liquid, so that particles composed of any one of the polymer materials D1,... Dn are dispersed on the liquid surface of the composite separation liquid, at the bottom of the composite separation liquid, or In addition to the horizontal distribution at the interface of the separated liquids, the interface particles (particles in which two kinds of high molecular materials among the polymeric materials D1,... Dn are joined) are horizontally distributed within the layer of each separated liquid. Process to make it.
(3) It is desired to recover a particle fraction composed of any one of the polymer materials D1,..., Dn horizontally distributed on the liquid surface of the composite separated liquid, the bottom of the composite separated liquid, or the interface of each separated liquid. A step of separating and collecting the particle fraction from other particles.
[0020]
In the above eighth invention, “fractionation of particles composed of any one of the polymer materials D 1,..., Dn” refers to fractionation of particles composed of only one of the polymer materials D 1,. This is a concept that does not include particles made of another kind of polymer material or interface particles in which any two kinds of polymer materials D1,..., Dn are joined.
[0021]
Also, with regard to the above-mentioned eighth invention, the same embodiment as the above-mentioned second invention to the fifth invention can be constituted with the same operation and effect as the second invention to the fifth invention.
[0022]
[Action and Effect of the Invention]
(Operations and effects of the first invention)
In the first invention, a laminate in which the polymer material layer made of the polymer material A1 and the polymer material layer made of the polymer material A2 are joined is crushed into fine particles, and in that case, reinforcement is performed if necessary. The lint originating from the yarn layer is selected and eliminated, and the particles are suspended in a separation liquid having a predetermined specific gravity, so that the particles composed of the polymer material A1 and the particles composed of the polymer material A2 are separated. Since the interfacial particles made of the material are horizontally distributed in a pure state at sites separated from each other in the separation liquid, the respective particle fractions can be easily separated and recovered by appropriate means.
[0023]
Therefore, most of the A1 material and the A2 material can be easily separated and recovered in a pure state (that is, excluding the particle fraction of the interface particles) by a simple and low-cost method called pulverization and specific gravity selection. And even if the A1 material layer and the A2 material layer are firmly vulcanized and bonded, the method can be carried out without any trouble. Even if the A1 material layer and / or the A2 material layer is formed thin, the particle size of the pulverization is correspondingly adjusted. By making the material layer fine, most of the thinly formed material layer can be easily separated and collected in a pure state.
[0024]
In addition, as a specific gravity selection method of particles, a separation method using a gas (air) utilizing a cyclone or the like as a separation medium is known. However, in this case, it is difficult to expect a high separation efficiency between the polymer material particles whose difference in specific gravity is not so large. In addition, the influence of factors (particle diameter and particle shape) other than the specific gravity of the particles is large, and it is difficult to separate and recover the polymer material particles in a pure state.
[0025]
The A1 material and / or A2 material thus separated and recovered according to the first invention are subjected to, for example, a regeneration process for returning to an unvulcanized state as it is, or after a certain material deterioration recovery process, or when it is a rubber material. After that, it can be used again as a molding material. The recovered particles can be used as they are, for example, as a filler. Of course, it is also possible to provide for thermal recycling.
[0026]
(Operation and effect of the second invention)
In the method for separating and recovering a laminated polymer material according to the first aspect of the present invention, the polymer material A1 and / or the polymer material A2 is a rubber material, and the material layer is formed of another polymer material layer. It is particularly preferably applied when vulcanization bonding is performed.
[0027]
(Operation and Effect of Third Invention)
The method for separating and recovering a laminated polymer material according to the first aspect of the present invention is a method for separating and recovering the polymer material A1 and / or the polymer material A2 from the viewpoint of cost or disposal due to the reasons described above. Is particularly preferably applied when the material layer is formed to a thickness of 1.0 mm or less.
[0028]
(Operation and effect of the fourth invention)
A preferred example of the laminate to be subjected to the method for separating and recovering a laminate polymer material includes a fluid transport hose or tube.
[0029]
(Function / Effect of Fifth Invention)
With respect to the step (1) of pulverizing the laminate into fine particles as described in the first invention, the pulverization means is particularly preferably freeze-pulverization of the laminate, and pulverization is carried out from coarse pulverization to fine pulverization using an appropriate means. It is particularly preferable to carry out in two or more stages up to the pulverization, and it is also particularly preferable to classify and pulverize the pulverized particles with a vibrating sieve or the like. The classified excessive particles can be subjected to another pulverizing treatment. The selection and elimination of the yarn waste derived from the reinforcing yarn layer in the first invention can be preferably performed at the time of this classification and selection.
[0030]
(Operation and effect of the sixth invention)
In the sixth invention, the same effect as in the first invention is obtained when the laminate is composed of two polymer material layers, and also when the laminate is composed of three or more polymer material layers, Each of the polymer materials B1,..., Bn constituting each polymer material layer can be easily separated and recovered in a pure state while excluding the interface particles where two or more materials are joined.
[0031]
(Operation and effect of the seventh invention)
In the seventh invention, the same effect as in the first invention is obtained when the laminate is composed of two polymer material layers, and also when the laminate is composed of three or more polymer material layers, Each of the polymer materials B1,..., Bn constituting each polymer material layer can be easily separated and recovered in a pure state while excluding the interface particles where two or more materials are joined.
[0032]
Compared with the above-described sixth invention, which can expect similar effects, the composition of the separation solution and the steps of separating and recovering each particle fraction are slightly complicated, but the polymer materials B1, There is an advantage that particles of Bn can be separated and recovered by one-time specific gravity selection using a separation liquid.
[0033]
(Operation and effect of the eighth invention)
In the eighth invention, in a case where two to many polymer material layers are laminated in an arbitrary order and only a material of a specific polymer material layer is to be separated and recovered in a pure state, the separation is performed. There is an advantage that separation and recovery can be performed by one-time specific gravity selection using the separation solution without complicating the structure of the liquid and the steps of separating and recovering each particle fraction.
[0034]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, embodiments of the first to eighth inventions will be described. In the following, when simply saying "the present invention", the first to eighth inventions are collectively indicated.
[0035]
[Embodiments common to the first to eighth inventions]
(Laminate and polymer material)
The laminate according to the present invention is a laminate in which a polymer material layer is bonded directly or via a reinforcing yarn layer, and at least the specific gravity of the polymer material to be separated and recovered is different from other polymer materials. Things. As a preferred embodiment of the laminated body, as in the first invention, a polymer material layer made of a polymer material A1 having a relatively small specific gravity α1 and a polymer material A2 showing a relatively large specific gravity α2 are formed. A laminate in which a polymer material layer is bonded can be exemplified.
[0036]
As another preferred embodiment of the laminate, two or more layers of polymer materials B1, B2,... Bn each having an arbitrary specific gravity β1, β2,. A laminate in which molecular material layers are joined directly in any order or via a reinforcing yarn layer can also be exemplified. Further, as in the seventh and eighth inventions, the polymer materials C1, C2,... Cn (.gamma.1, .gamma.2,... Γn (δ1, δ2,. Dn, D2,... Dn) can also be exemplified as a laminate in which two or more polymer material layers each joined directly or in an arbitrary order via a reinforcing yarn layer.
[0037]
Polymer materials exhibit different specific gravities. Particularly, in a rubber material in which various kinds of fillers are compounded, even when the same polymer is used, the specific gravity differs depending on the content of the compound. Specific gravity of a rubber material that is practically used, for example, fluorine rubber (FKM) has a specific gravity of about 1.8 to 1.9, epichlorohydrin rubber (ECO), silicone rubber (Q), chloroprene rubber (CR), and the like. Has a specific gravity of about 1.4 to 1.6, and the specific gravity of acrylonitrile-butadiene rubber (NBR), acrylic rubber (ACM, AEM), ethylene propylene rubber (EPDM) and the like shows about 1.1 to 1.3. Examples of the resin material include a polyamide resin having a specific gravity of about 1.0 to 1.2, and a glass fiber reinforced polyamide resin having a specific gravity of about 1.3 to 1.5. Further, the fluororesin greatly differs depending on the kind of the material, and its specific gravity is in a range of about 1.7 to 2.2. Therefore, in most polymer material laminates, a specific gravity relationship between materials to which the present invention can be applied can be found.
[0038]
In these laminates, the form of bonding between the polymer material layers is not limited. That is, it also includes a bonding mode in which the bonding state can be relatively easily separated along the interface, such as a case where the bonding state is simply maintained by the adhesiveness of the polymer material or the like, or the bonding is performed with a normal adhesive. Also, a bonding form in which it is difficult to peel along the interface, such as a case where the rubber layer is bonded by vulcanization between the rubber layer and the rubber layer or between the rubber layer and the resin layer, is included. In the latter case, the merit of applying the present invention is greater.
[0039]
In such a bonding mode, the polymer material layers may be directly bonded to each other, or may be bonded to each other via an interface layer such as a reinforcing yarn layer or an adhesive layer. When the polymer material layers are joined with a reinforcing yarn layer interposed therebetween, as described later, it is preferable to perform a classification process capable of eliminating yarn waste derived from the reinforcing yarn layer after pulverizing the laminate. .
[0040]
Although the kind of the laminate is not limited, for example, a hose or a tube for fluid transportation, particularly a hose or a tube for an automobile, on which a rubber material layer and / or a resin material layer are laminated, is preferably exemplified. In these laminates, those having a reinforcing yarn layer interposed between polymer material layers are also objects of the present invention as described above. In addition, those having a metal thin film layer between polymer material layers can also be an object of the present invention. In this case, the metal thin film layer can be removed by classification and sorting after the pulverization of the laminate, and even when it is difficult, the particles including the metal thin film layer can be separated in the separation liquid as interface particles according to the specific gravity. Furthermore, the present invention can also be applied to a component including a hard-to-pulverize component such as a wire blade layer between polymer layers as long as the component can be peeled or removed in advance.
[0041]
The thickness of the polymer material layer of the laminate and the type of the polymer material constituting the polymer material layer are not limited. Regarding the thickness of the polymer material layer, the present invention is applied when the polymer material layer includes a polymer material layer formed to a thickness of 1.0 mm or less and the constituent material of the polymer material layer is to be separated and recovered. The merits of this are great. Regarding the polymer material constituting the polymer material layer, any kind of rubber material, resin material, and elastomer material are included, but the following first polymer materials are particularly advantageous in applying the present invention. To 3rd materials are exemplified.
First material: a material that can be easily crushed to an arbitrary particle size, for example, a rubber material or a resin material.
Second material: a material whose separation / recovery is desired for price reasons. For example, fluorine rubber, fluorosilicone rubber, fluorine resin.
Third material: A material that is desired to be separated and collected for reasons of disposal. For example, a rubber material or a resin material containing a high concentration of a halogen element such as chlorine or fluorine which is not suitable for thermal recycling. Examples thereof include chloroprene rubber, epichlorohydrin rubber, fluorine rubber, and various fluorine resins.
[0042]
(Pulverizing process of laminate)
The laminate is first crushed into fine particles. The method and means of pulverization are not limited. For example, the pulverization may be performed only once, or may be performed in two or more stages from coarse pulverization to fine pulverization. The laminate can be freeze-ground. As an example of a preferable pulverization form, the laminate can be roughly pulverized and finely pulverized by a crusher or a grinder in a frozen state. In the process of pulverization, the particles may be classified and screened with a sieve, a vibrating sieve, or the like, and the excessive particle fraction may be subjected to another pulverization. In the case where the laminate includes a reinforcing yarn layer, yarn waste derived from the reinforcing yarn layer can be eliminated in the classification and sorting process.
[0043]
Due to the pulverization of the laminate, particles consisting only of the constituent material of one of the polymer material layers and the interface particles constituting the interface between the layers of the laminate (the state in which the constituent materials of the different polymer material layers are joined together) Particles). Normally, interfacial particles are not targeted for recovery, and from this viewpoint, pulverization that reduces the total weight of interfacial particles (that is, to a smaller particle size) is preferable. On the other hand, pulverization to an excessively small particle size is not advantageous in terms of efficiency and cost, and generally it is difficult to quickly select a specific gravity in a separated liquid.
[0044]
The degree of pulverization may be arbitrarily determined in consideration of the above circumstances, but generally, the thickness of the thinnest polymer material layer constituting the laminate or the thickness of the polymer material layer to be separated / recovered is generally determined. On the other hand, it is preferable to grind to a particle size of about 1/5 to 1/10. For example, when the fluororubber layer to be separated and collected is a thin layer having a thickness of about 0.5 to 0.8 mm, it is preferable to pulverize the fluororubber layer to a particle size of 100 to 150 μm. According to the method of the present invention, the influence of the particle size on the separation of the particle fraction is small as compared with the above-mentioned method using a cyclone or the like, but the fact that the particle size is distributed over a certain narrow range is not considered. Absent.
[0045]
(Pulverized particle separation / recovery process)
The pulverized particles are suspended in a separation liquid having a specific gravity accommodated in a separation tank, so that particles and interface particles consisting only of the constituent materials of each polymer material layer are respectively separated from the separation liquid. Distribute horizontally at different heights. In suspending the pulverized particles in the separation liquid, it is also preferable to stir or vibrate by ultrasonic vibration or the like in order to prevent air bubbles from adhering to the pulverized particles.
[0046]
Then, the desired particle fraction is separated and collected by an appropriate means. The separation tank only needs to have a configuration capable of scooping or extracting the particle fraction distributed on the liquid surface, bottom, or intermediate portion in a state where the separation liquid is stored. For example, a structure including a plurality of openable and closable shutters that can partition a separation tank at an arbitrary height in a horizontal direction can be cited.
[0047]
When a laminate in which a polymer material layer made of a polymer material A1 having a relatively small specific gravity α1 and a polymer material layer made of a polymer material A2 having a relatively large specific gravity α2 are joined is crushed, a high Particles composed of the molecule A1 (particles A1), particles composed of the polymer material A2 (particles A2), and interface particles (A1 / A2 particles) in which both materials are bonded are generated. When these particles are suspended in a separation liquid having a specific gravity αX (α1 <αX <α2), A1 particles float on the surface of the separation liquid, and A2 particles settle at the bottom of the separation liquid, and A1 / A2 The particles are distributed with some spread in the middle part between the liquid surface and the bottom. Therefore, it is easy to scoop only the A1 particle fraction at the liquid surface or to extract only the A2 particle fraction at the bottom by appropriate means.
[0048]
As the separation liquid, various so-called organic solvents and inorganic solvents can be arbitrarily selected and used, paying attention to their specific gravity. By dissolving a certain solute in these solvents, it is possible to obtain a separated liquid having a specific gravity adjusted. For example, as a separation liquid for separating ECO particles having a specific gravity of about 1.5, FKM particles having a specific gravity of about 1.8, and these interface particles, hexafluorofluorocarbon having a specific gravity of 1.61 is used. Benzene or the like can be preferably used.
[0049]
As the separation liquid, a gas in a so-called supercritical state (for example, carbon dioxide gas or other inert gas) can also be preferably used. That is, when a carbon dioxide gas and polymer material particles are filled in a robust container capable of adjusting the pressure and temperature, and the specific gravity of the carbon dioxide gas is controlled to the above-mentioned αX by setting to a predetermined pressure and temperature, A1 particles and A2 particles And the specific gravity of the A1 / A2 particles can be selected in the same manner as described above.
[0050]
[Embodiments of sixth to eighth inventions]
According to the sixth to eighth inventions, in addition to the case where the laminate is composed of two polymer material layers, the case where the laminate is composed of three or more polymer material layers, It can be separated and recovered with high yield in a pure state.
[0051]
(Embodiment of the sixth invention)
The sixth invention is a particularly efficient method when it is desired to recover only a polymer material having a specific specific gravity in a laminate composed of two or three or more polymer material layers.
That is, two or more polymer material layers made of polymer materials B1,..., Bn each having an arbitrary specific gravity β1,..., Βn are joined in an arbitrary order directly or via a reinforcing yarn layer. The same pulverization step as in the first invention is performed on the laminated body, and any one of the following (1) to (3) is performed in the subsequent specific gravity selection step using the separated liquid.
[0052]
{Circle around (1)} When the specific gravity βx of the polymer material Bx is the smallest specific gravity among the polymer materials B1,... Bn, the specific gravity βx is larger than the specific gravity βx and is smaller than the specific gravity of the other polymer materials B1,. Using a separation liquid having a small specific gravity, only particles (Bx particles) composed of the polymer material Bx are horizontally distributed on the liquid surface of the separation liquid. The interface particles containing the polymer material Bx also have a higher specific gravity than the Bx particles and are not distributed on the liquid surface of the separation liquid, and can be separated from the Bx particles.
[0053]
{Circle around (2)} When the specific gravity βx of the polymer material Bx is the largest specific gravity among the polymer materials B1,... Bn, the specific gravity βx is smaller than the specific gravity βx and is smaller than the specific gravity of the other polymer materials B1,. Using a separation liquid having a large specific gravity, only particles (Bx particles) composed of the polymer material Bx are horizontally distributed at the bottom of the separation liquid. The interface particles containing the polymer material Bx also have a lower specific gravity than the Bx particles, so they are not distributed at the bottom of the separation liquid, and can be separated from the Bx particles.
[0054]
{Circle around (3)} When the specific gravity βx of the polymer material Bx is an arbitrary intermediate value in the polymer materials B1,..., Bn, a separation liquid having exactly the same specific gravity as the specific gravity βx is used. Only particles composed of the material Bx (Bx particles) are horizontally distributed at an intermediate portion between the liquid surface and the bottom of the separation liquid. The interface particles containing the polymer material Bx also have a specific gravity that does not match that of the Bx particles, so that they are distributed on the liquid surface or the bottom of the separated liquid and can be separated from the Bx particles.
[0055]
(Embodiment of the seventh invention)
The seventh aspect of the present invention is particularly effective when it is desired to separate and collect two or more polymer materials having different specific gravities by a simple device in a laminate composed of two or three or more polymer material layers. Is the way.
[0056]
That is, two or more polymer material layers composed of polymer materials C1,... Cn exhibiting sequentially increasing specific gravities γ1,... Γn are joined in any order directly or via a reinforcing yarn layer. A pulverization step similar to the first invention is performed on the laminated body thus obtained, and in a subsequent specific gravity selection step using the separation liquid, the same specific gravity selection step as the first invention is performed a plurality of times while selecting the specific gravity of the separation liquid. By repeating, the particle fractions of each specific gravity are separated and collected. Therefore, it is necessary to use two or more kinds of separated liquids having different specific gravities in a plurality of specific gravity selecting steps.
[0057]
However, in the case of using carbon dioxide gas in a supercritical state as described above, the specific gravity is continuously changed in a direction of gradually increasing (or in a direction of gradually decreasing) by setting the pressure and temperature, so that the smallest value is obtained. Separation / recovery can be continuously repeated sequentially from the polymer material having the specific gravity (or sequentially from the polymer material having the smallest specific gravity).
[0058]
(Eighth Embodiment of the Invention)
The eighth aspect of the present invention is particularly effective when two or more polymer materials having different specific gravities are to be separated and recovered by a single process in a laminate comprising two or three or more polymer material layers. Is the way.
[0059]
That is, two or more polymer material layers made of polymer materials D1,..., Dn exhibiting sequentially increasing specific gravities δ1,..., Δn are joined in any order directly or via a reinforcing yarn layer. A pulverization step similar to the first invention is performed on the laminated body thus obtained, and a composite separation liquid is used in a subsequent specific gravity selection step using the separation liquid. The composite separation liquid has different specific gravities δX, δY,... (Δ1 <δX <δ2, δ2 <δY <δ3,...), And a plurality of incompatible separation liquids are hierarchically separated into layers. It was done. Examples of the configuration of such a composite separation liquid include a combination of water and an oil liquid and a combination of water, an organic solvent, and an oil liquid.
[0060]
【Example】
(Example 1)
The laminated body 1 shown in FIG. 1 is a rubber hose for an automobile, in which an innermost layer 2 is made of FKM having a thickness of 0.5 mm, and an intermediate layer 3 made of ECO having a thickness of 1.0 mm is sequentially formed on the outer peripheral side thereof. It has a reinforcing thread layer 4 and a skin layer 5 made of ECO having a thickness of 1.5 mm.
[0061]
This laminate 1 was processed according to the flowchart shown in FIG. That is, first, in the coarse pulverizing step 6, the laminate 1 was coarsely pulverized to a particle size of about 1 to 2 mm using a crusher or the like. Next, the obtained rubber particles were frozen by a device using liquid nitrogen in a freezing step 7, and then finely pulverized in a fine pulverizing step 8 using a grinder so that the particle diameter became about 100 to 200 μm. Thereafter, under the condition that the frozen state of the pulverized particles was released, the particles were classified using a vibrating sieve in a classification step 9 to remove yarn waste derived from the reinforcing yarn layer 4. In the classifying step 9, coarse particles on a 100-mesh sieve (about 150 μm or more) were once collected, and an additional step of repeating step 8 was repeated for the coarse particles as necessary.
[0062]
The thus-prepared particle aggregate having a particle diameter of 100 to 150 μm was subjected to specific gravity selection in the separation liquid dispersion step 10. That is, the above-mentioned particle aggregate was put into the separation liquid 12 accommodated in the separation tank 11 shown in FIG. 3, stirred and suspended. Although not shown, the separation tank 11 includes means for scooping the separated liquid 12 at the liquid surface portion, and means for extracting the separated liquid 12 at the bottom toward the container bottom. Separation liquid 12 is the same as the above-mentioned hexafluorobenzene (C ₆ F ₆ ).
[0063]
After the above particle aggregate is suspended in the separation liquid 12 and left standing for about 1 minute, particles 13 made of ECO are deposited on the liquid surface of the separation liquid 12 as shown in FIG. The particles 14 made of FKM were distributed at the bottom of the sample, and the interface particles 15 in a state where ECO and FKM were joined were distributed at the intermediate portion of the separation liquid 12, respectively.
[0064]
Therefore, the fraction of the FKM particles 14 is extracted from the bottom of the separation tank 11, and the fraction of the ECO particles 13 is scooped from the liquid surface portion of the separation tank 11, so that the FKM and the ECO constituting the laminate 1 are separated. Was able to be separated and recovered in a pure state.
[0065]
(Example 2 and Comparative Example)
The particle aggregate prepared by the same process as in Example 1 was subjected to specific gravity separation using a supercritical carbon dioxide gas in a robust separation tank equipped with a mechanism similar to that of the separation layer 11 to obtain a laminate 1. Most of the FKM and ECO that constituted the above were separated and recovered.
[0066]
On the other hand, as a comparative example, sorting by a known cyclone method was attempted on a particle aggregate prepared by the same process as in Example 1. Further, with respect to the same laminate 1 as in Example 1, a separation method was also attempted in which the hose was cut open along the axial direction and forcedly developed in a flat shape, and the laminate was sliced along the interface with a thin cutter.
[0067]
Table 1 below shows the ranges of the respective recoveries of FKM and ECO based on the results of performing each of the above-described Example 1, Example 2, and Comparative Example a plurality of times.
[0068]
[Table 1]

[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating a laminate according to an example.
FIG. 2 is a diagram showing a flowchart of the first embodiment.
FIG. 3 is a cross-sectional view showing a simplified specific gravity selection process of Example 1.
[Explanation of symbols]
1 laminate
2 Innermost layer
3 Middle layer
4 Reinforcing yarn layer
5 Skin layer
6-10 processes
11 Separation tank
12 Separation liquid
13,14 particles
15 Interface particles

Claims

A polymer material layer made of a polymer material A1 having a relatively small specific gravity α1 and a polymer material layer made of a polymer material A2 having a relatively large specific gravity α2 are bonded directly or via a reinforcing yarn layer. A method for separating and recovering a polymer material for a laminate, comprising performing the following steps on the laminate thus obtained.
(1) A step of pulverizing the laminate into fine particles. This step includes selection and elimination of lint originating from the reinforcing yarn layer when the polymer material layer composed of the polymeric materials A1 and A2 is a laminate joined via the reinforcing yarn layer.
(2) The particles made of the polymer material A1 are suspended on the liquid surface of the separated solution by suspending the pulverized particles in a separation solution having a specific gravity αX satisfying α1 <αX <α2. A step of horizontally distributing the particles at the bottom of the separated liquid and the interfacial particles (particles in a state where the polymer materials A1 and A2 are bonded) at an intermediate portion between the liquid surface and the bottom of the separated liquid;
(3) Separating the particle fraction composed of the polymer material A1 distributed on the liquid surface of the separated liquid and / or the particle fraction composed of the polymeric material A2 distributed on the bottom of the separated liquid from other particle fractions And collecting.

The laminated polymer material according to claim 1, wherein at least one of the polymer material A1 and the polymer material A2 is a rubber material and is vulcanized and bonded to another polymer material layer. Separation and recovery method.

At least one of the polymer material A1 and the polymer material A2 is a material whose separation / recovery is desired for reasons of cost or disposal, and the material layer is formed to a thickness of 1.0 mm or less. 3. The method for separating and recovering a polymer material according to claim 1 or 2, wherein the method comprises the steps of:

4. The method according to claim 1, wherein the laminate is a fluid transport hose or tube.

The separation of the laminated polymer material according to any one of claims 1 to 4, wherein the step (1) satisfies at least one of the following conditions (4) to (6). Collection method.
(4) The step (1) is performed by freeze-grinding the laminate.
(5) The step (1) is performed in a plurality of stages from coarse pulverization to fine pulverization.
(6) Classifying the particles pulverized in the step (1) and performing necessary re-pulverization.

A laminate in which two or more polymer material layers made of polymer materials B1,... Bn each exhibiting an arbitrary specific gravity β1,... Βn are joined in an arbitrary order directly or via a reinforcing yarn layer. A method for separating and recovering a laminated polymer material, comprising performing the following steps on a body to separate and collect particles made of the polymer material Bx having a specific gravity βx desired to be recovered.
(1) A step of pulverizing the laminate into fine particles. This step includes selection and elimination of yarn waste derived from the reinforcing yarn layer when the laminate includes the reinforcing yarn layer.
(2) The pulverized particles are suspended in a separation liquid having a predetermined specific gravity by any of the following methods (1) to (3), and the particles composed of the polymer material Bx having a specific gravity βx are replaced with other particles. Separating from fractionation.
{Circle around (1)} When the specific gravity βx of the polymer material Bx is the smallest specific gravity among the polymer materials B1,... Bn, the specific gravity βx is larger than the specific gravity βx and is smaller than the specific gravity of the other polymer materials B1,. Using a separation liquid having a small specific gravity, only particles composed of the polymer material Bx are horizontally distributed on the liquid surface of the separation liquid.
{Circle around (2)} When the specific gravity βx of the polymer material Bx is the largest specific gravity among the polymer materials B1,... Bn, the specific gravity βx is smaller than the specific gravity βx and is smaller than the specific gravity of the other polymer materials B1,. Using a separation liquid having a large specific gravity, only particles composed of the polymer material Bx are horizontally distributed at the bottom of the separation liquid.
{Circle around (3)} When the specific gravity βx of the polymer material Bx is an arbitrary intermediate value in the polymer materials B1,..., Bn, a separation liquid having exactly the same specific gravity as the specific gravity βx is used. Only the particles composed of the material Bx are horizontally distributed at an intermediate portion between the liquid level and the bottom of the separated liquid.
(3) a step of collecting a particle fraction composed of the polymer material Bx having the above specific gravity βx.

Two or more polymer material layers composed of polymer materials C1,... Cn exhibiting sequentially increasing specific gravities γ1,... Γn are joined in any order directly or via a reinforcing yarn layer. A method for separating and collecting a polymer material for a laminate, comprising performing the following steps on the laminate.
(1) A step of pulverizing the laminate into fine particles. This step includes selection and elimination of yarn waste derived from the reinforcing yarn layer when the laminate includes the reinforcing yarn layer.
(2) By suspending the pulverized particles in a separation liquid having a specific gravity between γ1 and γn, a relatively low-specific-gravity particle fraction horizontally distributed on the liquid surface of the separation liquid is obtained. A step of separating and collecting a relatively high-specific-gravity particle fraction horizontally distributed at the bottom of the liquid and an intermediate-specific-particle fraction horizontally distributed at an intermediate portion between the liquid surface and the bottom of the separated liquid.
(3) Among the particle fractions collected in the above (2), particles or interface particles composed of any one of the polymer materials C1,... Cn (state in which any two kinds of the polymer materials are joined) Of the particles containing two or more kinds of particles in the same manner as the above (2), which is suspended in a separation liquid having an intermediate specific gravity between these two or more kinds of particles. Is repeated until a particle fraction containing only particles composed of any of the polymer materials C1,... Cn is obtained, and all of the particle fractions composed of the polymer materials C1,. Alternatively, a step of separating and collecting only the particle fraction desired to be collected.

Two or more polymer material layers composed of polymer materials D1,..., Dn exhibiting sequentially increasing specific gravities δ1,... Δn are joined in any order directly or via a reinforcing yarn layer. A method for separating and collecting a polymer material for a laminate, comprising performing the following steps on the laminate.
(1) A step of pulverizing the laminate into fine particles. This step includes selection and elimination of yarn waste derived from the reinforcing yarn layer when the laminate includes the reinforcing yarn layer.
(2) Separated liquids having a specific gravity δX satisfying δ1 <δX <δ2, separated liquids having specific gravity δX satisfying δ1 <δX <δ2, respectively, Are suspended in a layered composite separation liquid, so that particles composed of any one of the polymer materials D1,... Dn are dispersed on the liquid surface of the composite separation liquid, at the bottom of the composite separation liquid, or In addition to the horizontal distribution at the interface of the separated liquids, the interface particles (particles in which two kinds of high molecular materials among the polymeric materials D1,... Dn are joined) are horizontally distributed within the layer of each separated liquid. Process to make it.
(3) It is desired to recover a particle fraction composed of any one of the polymer materials D1,..., Dn horizontally distributed on the liquid surface of the composite separated liquid, the bottom of the composite separated liquid, or the interface of each separated liquid. A step of separating and collecting the particle fraction from other particles.