JP2005264087A - Molding using polylactic acid - Google Patents

Molding using polylactic acid Download PDF

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JP2005264087A
JP2005264087A JP2004082015A JP2004082015A JP2005264087A JP 2005264087 A JP2005264087 A JP 2005264087A JP 2004082015 A JP2004082015 A JP 2004082015A JP 2004082015 A JP2004082015 A JP 2004082015A JP 2005264087 A JP2005264087 A JP 2005264087A
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polylactic acid
acid
lactide
pellets
molding
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JP4403845B2 (en
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Hitoshi Tomita
斉 冨田
Masayuki Furuya
正之 古屋
Akihiro Kuribayashi
昭博 栗林
Kiyomichi Ninomiya
清道 二之宮
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Toray Industries Inc
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Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly transparent molding by using polylactic acid. <P>SOLUTION: The molding is produced by using polylactic acid containing at most 0.15% lactide. Desirably, the polylactic acid shows a relative viscosity of 2.5 to 3.7 when measured at 20°C in a solution prepared by dissolving the polylactic acid in a mixed phenol/tetrachloroethane solvent (phenol/tetrachloroethane weight ratio=6/4) to a concentration of 10 g/liter. This molding has a high transparency and is desirable for packaging containers. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

本発明は、ラクチドの含有量が少ないポリ乳酸を用いた成形品に関する。   The present invention relates to a molded article using polylactic acid having a low lactide content.

ポリ乳酸は、自然環境下で分解するため生分解性プラスチックとして注目されており、一軸、二軸延伸フィルムや繊維、射出成形品などとして種々の用途にも用いられている。   Polylactic acid is attracting attention as a biodegradable plastic because it decomposes in a natural environment, and it is also used in various applications such as uniaxial and biaxially stretched films, fibers, and injection molded products.

このようなポリ乳酸の製造法には、乳酸を直接脱水縮合して目的物を得る直接法と、乳酸から一旦環状ラクチド(二量体)を合成し、晶析法などにより精製を行い、ついで開環重合を行う方法がある。このようにして得られたポリ乳酸には、ラクチドが多量に含有している。   Such polylactic acid can be produced by directly dehydrating and condensing lactic acid to obtain the desired product, synthesizing cyclic lactide (dimer) from lactic acid, and purifying it by crystallization. There is a method of performing ring-opening polymerization. The polylactic acid thus obtained contains a large amount of lactide.

しかしながら、この様なポリ乳酸を使用して成形品を製造すると、得られた成形品の透明性は不充分であり、中身を見せることを重視する様なパッケージや筐体等透明性を重視する用途には使用できないものであった。   However, when such a polylactic acid is used to produce a molded product, the resulting molded product has insufficient transparency, and importance is placed on the transparency of packages and housings that place importance on showing the contents. It could not be used for the purpose.

そのため、ラクチドの含有量を低減したものが提案されており、例えば特許文献1には、乳酸を直接重合あるいはラクチドを開環重合して製造したポリ乳酸ペレットを結晶化する工程と、該結晶化した固形のポリ乳酸ペレットより低分子物質をガス化除去する工程を経ることによって低分子物質を除去する方法が記載されている。しかし、この方法で得られたポリ乳酸のラクチドの含有量は約1%であり、これを用いて製造された成形品の透明性の透明性は包装容器としては不充分である。   For this reason, those having a reduced lactide content have been proposed. For example, Patent Document 1 discloses a step of crystallizing polylactic acid pellets produced by direct polymerization of lactic acid or ring-opening polymerization of lactide, and the crystallization. A method for removing low molecular weight substances by gasifying and removing low molecular weight substances from solid polylactic acid pellets is described. However, the content of lactide of polylactic acid obtained by this method is about 1%, and the transparency of the molded product produced using this is insufficient as a packaging container.

特開平9−095531号公報JP-A-9-095531

そこで、本発明は、ポリ乳酸を用いた透明性の優れた成形品を提供することを目的とする。   Accordingly, an object of the present invention is to provide a molded article having excellent transparency using polylactic acid.

上記目的は、ラクチドの含有率が0.15%以下であるポリ乳酸からなることを特徴とする成形品によって達成される。   The above object is achieved by a molded product comprising polylactic acid having a lactide content of 0.15% or less.

本発明の成形品は、透明性が高く、包装容器に好適である。   The molded product of the present invention has high transparency and is suitable for a packaging container.

本発明に用いるポリ乳酸とは具体的には、乳酸ホモポリマー及び乳酸コポリマーのことである。   Specifically, polylactic acid used in the present invention is a lactic acid homopolymer or a lactic acid copolymer.

本発明に使用する乳酸ポリマーは、L−乳酸単位、D−乳酸単位の構成モル比L/Dは100/0〜0/100のいずれであってもよいが、高い融点を得るにはL−乳酸あるいはD−乳酸いずれかの単位を90モル%以上、さらに高い融点を得るにはL−乳酸あるいはD−乳酸いずれかの単位を95モル%以上含むことが好ましい。   The lactic acid polymer used in the present invention may have a constitutional molar ratio L / D of L-lactic acid units and D-lactic acid units of 100/0 to 0/100. It is preferable to contain 90 mol% or more of either lactic acid or D-lactic acid, and 95 mol% or more of either L-lactic acid or D-lactic acid to obtain a higher melting point.

乳酸コポリマーは、乳酸モノマーまたはラクチドと共重合可能な他の成分とが共重合されたものである。このような他の成分としては、2個以上のエステル結合形成性の官能基を持つものが挙げられる。   The lactic acid copolymer is obtained by copolymerizing a lactic acid monomer or other component copolymerizable with lactide. Examples of such other components include those having two or more ester bond-forming functional groups.

具体的には、コハク酸、アジピン酸、アゼライン酸、セバシン酸、テレフタル酸、イソフタル酸等のジカルボン酸、芳香族多価アルコール、脂肪族多価アルコール、エーテルグリコール等の多価アルコール、グリコール酸、3−ヒドロキシ酪酸、4−ヒドロキシ酪酸、4−ヒドロキシ吉草酸、5−ヒドロキシ吉草酸、6−ヒドロキシカプロン酸等のヒドロキシカルボン酸等が挙げられる。   Specifically, dicarboxylic acids such as succinic acid, adipic acid, azelaic acid, sebacic acid, terephthalic acid, isophthalic acid, polyhydric alcohols such as aromatic polyhydric alcohol, aliphatic polyhydric alcohol, ether glycol, glycolic acid, Examples thereof include hydroxycarboxylic acids such as 3-hydroxybutyric acid, 4-hydroxybutyric acid, 4-hydroxyvaleric acid, 5-hydroxyvaleric acid, and 6-hydroxycaproic acid.

ポリ乳酸は、従来公知の方法で合成することができる。具体的には、乳酸からの直接重合、または乳酸環状二量体ラクチドの開環重合によって合成することができる。開環重合では、より高分子量のものを得ることができる。   Polylactic acid can be synthesized by a conventionally known method. Specifically, it can be synthesized by direct polymerization from lactic acid or ring-opening polymerization of lactic acid cyclic dimer lactide. In the ring-opening polymerization, a higher molecular weight can be obtained.

直接重合を行なう場合、L−乳酸、D−乳酸、DL−乳酸、またはこれらの混合物のいずれの乳酸を用いても良い。また、開環重合を行なう場合においても、L−ラクチド、D−ラクチド、DL−ラクチド、メソ−ラクチドまたはこれらの混合物のいずれのラクチドを用いても良い。   When direct polymerization is performed, any lactic acid of L-lactic acid, D-lactic acid, DL-lactic acid, or a mixture thereof may be used. Also, in the case of carrying out ring-opening polymerization, any lactide of L-lactide, D-lactide, DL-lactide, meso-lactide or a mixture thereof may be used.

この重合反応に用いる触媒は特に限定されるものではないが、公知の乳酸重合用触媒を用いることができる。触媒の使用量は、一般にラクチド100重量部に対して0.001〜5重量部程度である。   Although the catalyst used for this polymerization reaction is not particularly limited, a known catalyst for lactic acid polymerization can be used. The amount of the catalyst used is generally about 0.001 to 5 parts by weight with respect to 100 parts by weight of lactide.

重合反応は、上記触媒の存在下、触媒種によっても異なるが通常100〜200℃の温度で行うことができる。   The polymerization reaction can be usually performed at a temperature of 100 to 200 ° C. in the presence of the catalyst, although it varies depending on the catalyst type.

本発明のポリ乳酸から作られた成形品は、0.15%以下のラクチドを含有しているポリ乳酸であることが肝要であり、特に、0.13%以下が好ましい。   It is important that the molded article made from the polylactic acid of the present invention is a polylactic acid containing 0.15% or less of lactide, and particularly preferably 0.13% or less.

ラクチドの含有量が0.15%を超えるポリ乳酸の場合、得られる成形品の透明性は不充分である。   In the case of polylactic acid having a lactide content of more than 0.15%, the resulting molded article has insufficient transparency.

このようなポリ乳酸を製造する方法は、重合されペレット状に成型されたポリ乳酸を温水に浸漬させる方法などがある。以下にその一例を示す。   As a method for producing such polylactic acid, there is a method of immersing polylactic acid that has been polymerized and formed into pellets in warm water. An example is shown below.

ペレットの形状としては、粉砕状、角形チップ状、円柱状、マーブル状などの形状に特定の必要はないが、円柱状かマーブル状が好ましい。ペレットの大きさに関しては特に指定は無いが、ペレットの袋詰めなど製造工程におけるハンドリングおよび二次成形の際のハンドリングを考慮すると、形状に関わらず、ペレット100個当たり0.1〜10g好ましくは1〜5gである。   The shape of the pellet is not particularly required to be a pulverized shape, a square chip shape, a cylindrical shape, a marble shape, or the like, but a cylindrical shape or a marble shape is preferable. The size of the pellet is not particularly specified, but in consideration of handling in the manufacturing process such as bagging of pellets and handling in the secondary forming, 0.1 to 10 g per 100 pellets, preferably 1 regardless of the shape. ~ 5g.

このようにして得られたポリ乳酸のペレットを温水に浸漬させる。その際、低分子量物質を効率よく除去するためにペレットを攪拌したり温水を対流させることが好ましい。また、浴比は特に限定されないが、ペレットが温水に充分に浸漬する必要がある。効率的に低分子量物質を除去するためにはポリ乳酸ペレットを重量で2倍以上の温水で浸漬することが好ましい。   The polylactic acid pellets thus obtained are immersed in warm water. At that time, in order to efficiently remove the low molecular weight substance, it is preferable to stir the pellets or to convect warm water. The bath ratio is not particularly limited, but the pellets need to be sufficiently immersed in warm water. In order to efficiently remove low molecular weight substances, it is preferable to immerse the polylactic acid pellets in warm water that is twice or more by weight.

浸漬時間が極端に長い場合、または、温水温度が極端に高い場合、ペレットの加水分解が進み樹脂の粘度が下がり、次工程で得られる成形品が脆くなる恐れがある。   When the immersion time is extremely long or the hot water temperature is extremely high, the hydrolysis of the pellet proceeds and the viscosity of the resin decreases, and the molded product obtained in the next step may become brittle.

温水に浸漬した後所定の時間に達したらすぐに脱水等をして冷却することが好ましい。   It is preferable to cool by dehydration or the like as soon as a predetermined time is reached after being immersed in warm water.

ポリ乳酸のペレットの相対粘度は、フェノールとテトラクロロエタンの混合溶剤(フェノール/テトラクロロエタンの重量比6/4)に10g/l溶解させて、測定温度が20℃の時に2.5〜3.7が好ましい。   The relative viscosity of the polylactic acid pellets is 2.5 to 3.7 when the measurement temperature is 20 ° C. by dissolving 10 g / l in a mixed solvent of phenol and tetrachloroethane (phenol / tetrachloroethane weight ratio 6/4). Is preferred.

相対粘度が2.5未満のポリ乳酸を使用して成形品を製造した場合、成形品は脆くなり、実用上耐えられない。また、3.7を超える場合、溶融粘度が高く、成形性が不良になる。また、温度を上げれば溶融粘度は下がるが、ポリ乳酸の熱分解に起因する低分子物質が生成され、得られた成形品の透明性は不良となる。 When a molded product is produced using polylactic acid having a relative viscosity of less than 2.5, the molded product becomes brittle and cannot be practically tolerated. On the other hand, if it exceeds 3.7, the melt viscosity is high and the moldability becomes poor. Further, when the temperature is raised, the melt viscosity is lowered, but a low-molecular substance resulting from the thermal decomposition of polylactic acid is produced, and the resulting molded product has poor transparency.

本発明の成形品とは具体的には、電気・電子機器に使用される筐体で特に内部構造を見せる透明な筐体、卵パック等のシートの熱成形品、シートカット板に罫線を付与して折り曲げて作った容器、液体を保存する容器、同時若しくは逐次の一軸若しくは二軸で延伸されたフィルム等を挙げることが出来る。   Specifically, the molded product of the present invention is a transparent housing that shows an internal structure in a housing used for electrical and electronic equipment, a thermoformed product of a sheet such as an egg pack, and a ruled line on a sheet cut plate And a container made by bending, a container for storing a liquid, a film stretched uniaxially or biaxially simultaneously or sequentially, and the like.

これらの成形品の製造方法は、射出成形、押出成形、ブロー成形、延伸フィルム成形のうちのいずれかの成形加工により成形されてなることが好ましい。   The manufacturing method of these molded products is preferably formed by any one of injection molding, extrusion molding, blow molding, and stretched film molding.

評価方法は以下に従った。
1.ラクチドの含有量 ガスクロマトグラフ(スプリットレス法)による。
GC装置:島津製作所製 GC−14A、検出器:FID、キャピラリーカラム:DB−17、キャリアガス:He、カラム温度:110℃(1min)―10℃/min―280℃(2min)、INJ温度:220℃、DET温度:300℃
2.相対粘度 フェノールとテトラクロロエタンの混合溶剤(フェノール/テトラクロロエタンの重量比6/4)に10g/l溶解させて、20℃で測定。
3.透明性 射出成形で4mm厚みの成形品を作製し、日本電色社製濁度計300Aを用いて濁度を評価した。
The evaluation method was as follows.
1. Lactide content According to gas chromatograph (splitless method).
GC apparatus: GC-14A manufactured by Shimadzu Corporation, detector: FID, capillary column: DB-17, carrier gas: He, column temperature: 110 ° C. (1 min) −10 ° C./min−280° C. (2 min), INJ temperature: 220 ℃, DET temperature: 300 ℃
2. Relative viscosity Measured at 20 ° C. by dissolving 10 g / l in a mixed solvent of phenol and tetrachloroethane (weight ratio of phenol / tetrachloroethane 6/4).
3. Transparency A molded product having a thickness of 4 mm was prepared by injection molding, and the turbidity was evaluated using a turbidimeter 300A manufactured by Nippon Denshoku Co., Ltd.

以下、実施例を挙げて本発明を説明するが、本発明はこの実施例に限定されない。   EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated, this invention is not limited to this Example.

実験例1〜8
10Lの丸底フラスコに表1に示す温度の水を4L入れ、開環重合で得られたポリ乳酸のペレット(ペレット100個当たり、2.2g)2kg加えて浸漬させた。ヒーターで表に示す温度と時間を維持して処理した。処理後、ペレットを濾別した後冷水で急冷し、真空乾燥機で100℃、24時間乾燥した。得られたペレットの相対粘度及びラクチドの含有量を測定した。さらに、住友重機械社製射出成形機で4mm厚みの射出成形品を作製し、濁度を評価した。その結果も表1に示した。
Experimental Examples 1-8
4 L of water having the temperature shown in Table 1 was placed in a 10 L round bottom flask, and 2 kg of polylactic acid pellets (2.2 g per 100 pellets) obtained by ring-opening polymerization were added and immersed. The treatment was carried out while maintaining the temperature and time shown in the table with a heater. After the treatment, the pellets were filtered off, quenched with cold water, and dried in a vacuum dryer at 100 ° C. for 24 hours. The relative viscosity and lactide content of the obtained pellets were measured. Furthermore, an injection molded product having a thickness of 4 mm was produced with an injection molding machine manufactured by Sumitomo Heavy Industries, Ltd., and turbidity was evaluated. The results are also shown in Table 1.

比較例1
実施例1で使用したペレットを温水で処理することなく実施例1と同様の条件で真空乾燥した。得られたペレットを実施例1と同様に相対粘度及びラクチドの含有量を測定した。
さらに、射出成形品を作製し、濁度を評価した。その結果も表1に示した。
Comparative Example 1
The pellets used in Example 1 were vacuum dried under the same conditions as in Example 1 without being treated with warm water. The relative viscosity and lactide content of the obtained pellets were measured in the same manner as in Example 1.
Furthermore, injection molded products were produced and turbidity was evaluated. The results are also shown in Table 1.

実施例9
ポリ乳酸樹脂のペレット(カーギルダウ社製 相対粘度)を表1に示す処理条件で温水処理し、実施例1と同様の条件で真空乾燥した。得られたペレットを実施例1と同様に相対粘度及びラクチドの含有量を測定した。
さらに、射出成形品を作製し、濁度を評価した。その結果も表1に示した。
Example 9
Polylactic acid resin pellets (Cargill Dow Relative Viscosity) were treated with warm water under the treatment conditions shown in Table 1 and vacuum dried under the same conditions as in Example 1. The relative viscosity and lactide content of the obtained pellets were measured in the same manner as in Example 1.
Furthermore, injection molded products were produced and turbidity was evaluated. The results are also shown in Table 1.

実施例10
実施例2で使用したペレットを東洋精機製作所社製ラボプラストミルで厚み0.3mmの未延伸シートを作製し、濁度を評価した。その結果、21.5%であった。
Example 10
An unstretched sheet having a thickness of 0.3 mm was prepared from the pellets used in Example 2 with a lab plast mill manufactured by Toyo Seiki Seisakusho, and turbidity was evaluated. As a result, it was 21.5%.

比較例2
比較例1で使用したペレットを実施例10と同様に厚み0.3mmの未延伸シートを作製し、濁度を評価した。その結果、31.2%であった。
Comparative Example 2
An unstretched sheet having a thickness of 0.3 mm was produced from the pellets used in Comparative Example 1 in the same manner as in Example 10, and the turbidity was evaluated. As a result, it was 31.2%.

実施例11
実施例10で作製した未延伸シートを東洋精機製作所社製二軸延伸装置で同時二軸延伸を行い、厚み75μm延伸フィルムを作製し、濁度を評価した。その結果、3.6%であった。
Example 11
The unstretched sheet prepared in Example 10 was simultaneously biaxially stretched with a biaxial stretching apparatus manufactured by Toyo Seiki Seisakusho Co., Ltd., to produce a 75 μm-thick stretched film, and turbidity was evaluated. As a result, it was 3.6%.

比較例3
比較例2で作製した未延伸シートを実施例11と同様に厚み75μm延伸フィルムを作製し、濁度を評価した。その結果、7.6%であった。
Comparative Example 3
A 75 μm-thick stretched film was produced from the unstretched sheet produced in Comparative Example 2 in the same manner as in Example 11, and the turbidity was evaluated. As a result, it was 7.6%.

実施例12
実施例2で使用したペレットを日本製鋼所社製ダイレクトブロー成形機で厚み1.0mmの容器を作製し、濁度を評価した。その結果、16.2%であった。
Example 12
A container having a thickness of 1.0 mm was prepared from the pellets used in Example 2 with a direct blow molding machine manufactured by Nippon Steel Works, and turbidity was evaluated. As a result, it was 16.2%.

比較例4
比較例1で使用したペレットを実施例2と同様に厚み1.0mmの容器を作製し、濁度を評価した。その結果、23.1%であった。
Comparative Example 4
A container having a thickness of 1.0 mm was prepared from the pellets used in Comparative Example 1 in the same manner as in Example 2, and the turbidity was evaluated. As a result, it was 23.1%.

本発明の成形品は、透明性が優れており、包装容器に適している。
The molded product of the present invention has excellent transparency and is suitable for a packaging container.

Claims (2)

ラクチドの含有率が0.15%以下であるポリ乳酸からなることを特徴とする成形品。 A molded article comprising polylactic acid having a lactide content of 0.15% or less. 上記ポリ乳酸がフェノールとテトラクロロエタンの混合溶剤(フェノール/テトラクロロエタンの重量比6/4)に10g/l溶解させて、測定温度が20℃の時の相対粘度が2.5〜3.7である請求項1項記載の成形品。
The polylactic acid is dissolved in a mixed solvent of phenol and tetrachloroethane (phenol / tetrachloroethane weight ratio 6/4) at 10 g / l, and the relative viscosity at a measurement temperature of 20 ° C. is 2.5 to 3.7. The molded article according to claim 1.
JP2004082015A 2004-03-22 2004-03-22 Method for producing polylactic acid with low lactide content Expired - Lifetime JP4403845B2 (en)

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Publication number Priority date Publication date Assignee Title
JP2010526200A (en) * 2007-05-04 2010-07-29 ベーリンガー インゲルハイム ファルマ ゲゼルシャフト ミット ベシュレンクテル ハフツング ウント コンパニー コマンディトゲゼルシャフト Method and apparatus for purifying absorbent polyester

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63254128A (en) * 1987-03-19 1988-10-20 ベーリンガー、インゲルハイム、カーゲー Method for refining absorbable polyester
JPH07228674A (en) * 1993-09-20 1995-08-29 Mitsui Toatsu Chem Inc Method for purifying aliphatic polyester
JPH08500131A (en) * 1992-06-19 1996-01-09 イーストマン ケミカル カンパニー Poly (3-hydroxyalkanoate) and method for producing the same
JP2551756B2 (en) * 1985-05-07 1996-11-06 武田薬品工業株式会社 Polyoxycarboxylic acid ester and method for producing the same
JPH08311175A (en) * 1995-05-17 1996-11-26 Shimadzu Corp Production of polylactate
JPH0995531A (en) * 1995-07-25 1997-04-08 Shimadzu Corp Method for removing monomer from polylactic acid and apparatus therefor
JPH09104745A (en) * 1995-10-06 1997-04-22 Shimadzu Corp Apparatus for removing monomer from polylactic acid and method for removing monomer therewith
JPH09309948A (en) * 1996-05-23 1997-12-02 Shimadzu Corp Production of biodegradable polyester
JP2001192446A (en) * 1999-10-27 2001-07-17 Mitsui Chemicals Inc Method for producing aliphatic polyester having excellent stability

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2551756B2 (en) * 1985-05-07 1996-11-06 武田薬品工業株式会社 Polyoxycarboxylic acid ester and method for producing the same
JPS63254128A (en) * 1987-03-19 1988-10-20 ベーリンガー、インゲルハイム、カーゲー Method for refining absorbable polyester
JPH08500131A (en) * 1992-06-19 1996-01-09 イーストマン ケミカル カンパニー Poly (3-hydroxyalkanoate) and method for producing the same
JPH07228674A (en) * 1993-09-20 1995-08-29 Mitsui Toatsu Chem Inc Method for purifying aliphatic polyester
JPH08311175A (en) * 1995-05-17 1996-11-26 Shimadzu Corp Production of polylactate
JPH0995531A (en) * 1995-07-25 1997-04-08 Shimadzu Corp Method for removing monomer from polylactic acid and apparatus therefor
JPH09104745A (en) * 1995-10-06 1997-04-22 Shimadzu Corp Apparatus for removing monomer from polylactic acid and method for removing monomer therewith
JPH09309948A (en) * 1996-05-23 1997-12-02 Shimadzu Corp Production of biodegradable polyester
JP2001192446A (en) * 1999-10-27 2001-07-17 Mitsui Chemicals Inc Method for producing aliphatic polyester having excellent stability

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010526200A (en) * 2007-05-04 2010-07-29 ベーリンガー インゲルハイム ファルマ ゲゼルシャフト ミット ベシュレンクテル ハフツング ウント コンパニー コマンディトゲゼルシャフト Method and apparatus for purifying absorbent polyester
US9156942B2 (en) 2007-05-04 2015-10-13 Evonik Roehm Gmbh Method and device for cleaning an absorptive polyester

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