JPH0631175A - Lactidation catalyst - Google Patents
Lactidation catalystInfo
- Publication number
- JPH0631175A JPH0631175A JP4187113A JP18711392A JPH0631175A JP H0631175 A JPH0631175 A JP H0631175A JP 4187113 A JP4187113 A JP 4187113A JP 18711392 A JP18711392 A JP 18711392A JP H0631175 A JPH0631175 A JP H0631175A
- Authority
- JP
- Japan
- Prior art keywords
- lactide
- lactic acid
- catalyst
- producing
- added
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts
Landscapes
- Heterocyclic Compounds That Contain Two Or More Ring Oxygen Atoms (AREA)
- Catalysts (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、より効率的にラクチド
を製造するのに有用な、ラクチド化触媒に関する。TECHNICAL FIELD The present invention relates to a lactide-forming catalyst useful for producing lactide more efficiently.
【０００２】[0002]
【従来の技術】ラクチドの開環重合によって得られるポ
リ乳酸はすでに医用分野等においては、例えば手術用縫
合糸、注射薬用マイクロカプセルのような生体分解性医
療材料として実用化されており、今後も広範囲に利用さ
れることが期待されている。2. Description of the Related Art Polylactic acid obtained by ring-opening polymerization of lactide has already been put to practical use in the medical field etc. as a biodegradable medical material such as surgical sutures and microcapsules for injection. It is expected to be widely used.
【０００３】ポリ乳酸の原料であるラクチドは、乳酸の
脱水反応によって得られる２量体であって、分子内環状
エステルの１種である。このようなラクチドを製造する
方法としては、通常、以下の方法が実施されている。Lactide, which is a raw material for polylactic acid, is a dimer obtained by the dehydration reaction of lactic acid and is one kind of intramolecular cyclic ester. As a method for producing such lactide, the following method is usually carried out.
【０００４】(1)乳酸を濃縮し、減圧下で加熱すること
により脱水反応を行って乳酸プレポリマー（ポリ乳酸オ
リゴマー）を得、次いで窒素ガス中、減圧下で加熱する
ことにより解重合させてラクチドに変換する方法。(1) Lactic acid is concentrated and dehydrated by heating under reduced pressure to obtain a lactic acid prepolymer (polylactic acid oligomer), which is then depolymerized by heating under reduced pressure in nitrogen gas. How to convert to lactide.
【０００５】(2)2-クロロプロピオン酸ナトリウムを加
熱してプレポリマー（D,L-体）に変換した後、窒素ガス
中、減圧下で加熱することにより解重合させてラクチド
を得る方法。(2) A method of obtaining lactide by heating sodium 2-chloropropionate to convert it into a prepolymer (D, L-form), and then depolymerizing it by heating in nitrogen gas under reduced pressure.
【０００６】しかし、上記(1)および(2)の方法は、乳酸
の濃縮に多量の熱量を消費し、解重合が高温を要し、か
つ反応速度が低いために非効率である、等の欠点があ
る。またこれらの方法によって得られたラクチドは、一
般に吸湿性であるために、取扱が困難であり、上記工程
において不可避な吸水に伴う品質低下、収量低下等の問
題もあった。However, the above methods (1) and (2) consume a large amount of heat for concentrating lactic acid, require high temperature for depolymerization, and are inefficient because the reaction rate is low. There are drawbacks. Further, the lactide obtained by these methods is generally hygroscopic and thus difficult to handle, and there are problems such as quality deterioration and yield decrease due to water absorption which is unavoidable in the above process.
【０００７】[0007]
【発明が解決しようとする課題】上記問題点を解決する
ために、本発明の目的は、多量の熱量を使用せず、かつ
吸湿性の少ないラクチドを効率よく製造するのに、優れ
た触媒効果を発揮するラクチド化触媒を提供することに
ある。In order to solve the above problems, an object of the present invention is to provide an excellent catalytic effect in efficiently producing lactide which does not use a large amount of heat and has a low hygroscopicity. It is to provide a lactide-forming catalyst that exerts
【０００８】[0008]
【課題を解決するための手段】本発明の第１のラクチド
化触媒は、乳酸プレポリマーまたは乳酸エステルからラ
クチドを製造する工程で添加する触媒であって、下記一
般式〔I〕で表されるジブチル錫化合物であり、そのこ
とにより上記目的が達成される。The first lactide-forming catalyst of the present invention is a catalyst added in the step of producing lactide from a lactic acid prepolymer or a lactic acid ester and is represented by the following general formula [I]. It is a dibutyltin compound, which achieves the above object.
【０００９】[0009]
【化２】 [Chemical 2]
【００１０】（式中、Ａ1およびＡ2は、それぞれ独立し
て、フッ素原子、塩素原子、臭素原子、アセトキシ基、
2-ヒドロキシプロピオニルオキシ基、メタンスルホニル
オキシ基またはトルエンスルホニルオキシ基を表すか、
あるいは−Ａ1および−Ａ2を併せて＝Ｏを表す）。(In the formula, A 1 and A 2 are each independently a fluorine atom, a chlorine atom, a bromine atom, an acetoxy group,
Represents a 2-hydroxypropionyloxy group, a methanesulfonyloxy group or a toluenesulfonyloxy group,
Alternatively, -A 1 and -A 2 together represent = 0).
【００１１】本発明の第２のラクチド化触媒は、乳酸プ
レポリマーまたは乳酸エステルからラクチドを製造する
工程で添加する触媒であって、五酸化リンまたは三酸化
リンであり、そのことにより上記目的が達成される。The second lactide-forming catalyst of the present invention is a catalyst added in the step of producing a lactide from a lactic acid prepolymer or a lactic acid ester, and is phosphorus pentoxide or phosphorus trioxide. To be achieved.
【００１２】本発明の第３のラクチド化触媒は、乳酸プ
レポリマーまたは乳酸エステルからラクチドを製造する
工程で添加する触媒であって、上記一般式〔I〕で表さ
れるジブチル錫化合物と、五酸化リンまたは三酸化リン
とを組み合わせてなり、そのことにより上記目的が達成
される。The third lactide-forming catalyst of the present invention is a catalyst added in the step of producing lactide from a lactic acid prepolymer or a lactic acid ester, and comprises a dibutyltin compound represented by the above general formula [I], In combination with phosphorus oxide or phosphorus trioxide, the above object is achieved.
【００１３】以下、本発明について詳しく説明する。The present invention will be described in detail below.
【００１４】本発明のラクチド化触媒は、下記式〔II〕
および下記式〔III〕に示すラクチド化反応において使
用される。The lactide-forming catalyst of the present invention has the following formula [II]
And in the lactide-forming reaction represented by the following formula [III].
【００１５】[0015]
【化３】 [Chemical 3]
【００１６】（式中、ｎは、2〜500の整数を表す。）(In the formula, n represents an integer of 2 to 500.)
【００１７】[0017]
【化４】 [Chemical 4]
【００１８】（式中、Ｒは炭素原子数1〜6の低級アルキ
ル基を表す。）上記式〔II〕の反応は、乳酸プレポリマ
ーを解重合させるラクチド化であり、上記式〔III〕の
反応は乳酸エステルのエステル交換反応によって2分子
を環化縮合させるラクチド化である。(In the formula, R represents a lower alkyl group having 1 to 6 carbon atoms.) The reaction of the above formula [II] is a lactide reaction for depolymerizing the lactic acid prepolymer, and the reaction of the above formula [III] The reaction is a lactide reaction in which two molecules are cyclocondensed by transesterification of lactate.
【００１９】本発明の第１のラクチド化触媒は、上記一
般式〔I〕で表されるジブチル錫化合物である。上記一
般式〔I〕において、Ａ1およびＡ2は、それぞれ１価の
酸基が好ましく、具体的な化合物としては、ジブチル錫
ジクロライド、ジブチル錫ラクタート等が挙げられる。
Ａ1およびＡ2は、１個の２価の基であってもよく、例え
ばジブチル錫オキサイドが含まれる。また、上記触媒
は、乳酸プレポリマーまたは乳酸エステルに対して0.01
〜2重量％の範囲で添加されるのが好ましい。上記添加
量が0.01重量％未満の場合は、触媒効果が不十分である
ため、好ましくなく、また上記添加量が2重量％を超え
る場合、触媒効果の向上が認められないため、好ましく
ない。The first lactide-forming catalyst of the present invention is a dibutyltin compound represented by the above general formula [I]. In the above general formula [I], A 1 and A 2 are preferably monovalent acid groups, and specific compounds include dibutyltin dichloride and dibutyltin lactate.
A 1 and A 2 may be one divalent group and include, for example, dibutyltin oxide. Further, the catalyst is 0.01% with respect to the lactic acid prepolymer or lactate
It is preferably added in the range of 2 wt%. If the addition amount is less than 0.01% by weight, the catalytic effect is insufficient, which is not preferable. If the addition amount exceeds 2% by weight, the catalytic effect cannot be improved, which is not preferable.
【００２０】本発明の第２のラクチド化触媒は、五酸化
リンまたは三酸化リンである。また、上記触媒は、乳酸
プレポリマーまたは乳酸エステルに対して0.01〜5重量
％の範囲で添加されるのが好ましい。上記添加量が0.01
重量％未満の場合は、触媒効果が不十分であるため、好
ましくなく、また上記添加量が5重量％を超える場合、
触媒効果の向上が認められないため、好ましくない。The second lactide-forming catalyst of the present invention is phosphorus pentoxide or phosphorus trioxide. The catalyst is preferably added in the range of 0.01 to 5% by weight based on the lactic acid prepolymer or lactic acid ester. The above addition amount is 0.01
If it is less than 5% by weight, the catalytic effect is insufficient, so that it is not preferable, and if the addition amount exceeds 5% by weight,
It is not preferable because improvement of the catalytic effect is not observed.
【００２１】本発明の第３のラクチド化触媒は、上記一
般式〔I〕で表されるジブチル錫化合物と、五酸化リン
または三酸化リンとを組み合わせてなり、この場合、そ
の触媒効果は著しく増強する。また、上記触媒は、乳酸
プレポリマーまたは乳酸エステルに対して0.01〜5重量
％の範囲で添加されるのが好ましい。上記添加量が0.01
重量％未満の場合は、触媒効果が不十分であるため、好
ましくなく、また上記添加量が5重量％を超える場合に
は、触媒効果の向上が認められないため、好ましくな
い。The third lactide-forming catalyst of the present invention comprises a combination of the dibutyltin compound represented by the above general formula [I] and phosphorus pentoxide or phosphorus trioxide. In this case, the catalytic effect is remarkable. Strengthen. The catalyst is preferably added in the range of 0.01 to 5% by weight based on the lactic acid prepolymer or lactic acid ester. The above addition amount is 0.01
When it is less than 5% by weight, the catalytic effect is insufficient, which is not preferable, and when the addition amount exceeds 5% by weight, the catalytic effect is not improved, which is not preferable.
【００２２】上記式〔II〕の工程においては、原料の乳
酸プレポリマーに、本発明の触媒を添加し、減圧（700
〜10mmHg）にして160〜220℃に加熱する。反応時間は2
〜10時間である。その後、減圧度を上げ（10〜0.5mmH
g）、90〜110℃の温度範囲で留出されるラクチドを得
る。In the step of the above formula [II], the catalyst of the present invention is added to the lactic acid prepolymer as a raw material, and the pressure reduction (700
~ 10mmHg) and heat to 160-220 ℃. Reaction time is 2
~ 10 hours. After that, increase the decompression degree (10 to 0.5 mmH
g), obtaining lactide which is distilled over in the temperature range of 90-110 ° C.
【００２３】上記工程において原料の乳酸プレポリマー
は、以下の方法で製造し得る。まず、乳酸を200℃で常
温または減圧で加熱する。反応時間は減圧度に依存する
が、常温では15〜20時間である。この反応により分子量
数千のプレポリマーが得られる。また、上記式〔III〕
の工程においては、原料の乳酸エステルに、本発明の触
媒を添加し、減圧（700〜100mmHg）にして120〜220℃に
加熱する。反応時間は2〜10時間である。その後、減圧
度を上げ（10〜0.5mmHg）、90〜110℃の温度範囲で留出
されるラクチドを得る。なお、上記反応で生成するアル
コールは、分留塔を付した装置を使用して反応中に留出
させることができる。The lactic acid prepolymer as a raw material in the above step can be produced by the following method. First, lactic acid is heated at 200 ° C. at room temperature or under reduced pressure. The reaction time is 15 to 20 hours at room temperature, depending on the degree of vacuum. By this reaction, a prepolymer having a molecular weight of several thousand is obtained. Further, the above formula [III]
In the step (1), the catalyst of the present invention is added to the raw material lactic acid ester, the pressure is reduced (700 to 100 mmHg), and the mixture is heated to 120 to 220 ° C. The reaction time is 2 to 10 hours. Then, the degree of vacuum is increased (10 to 0.5 mmHg) to obtain lactide that is distilled in the temperature range of 90 to 110 ° C. The alcohol produced in the above reaction can be distilled during the reaction by using an apparatus equipped with a fractionating column.
【００２４】上記工程において原料の乳酸エステルは、
以下の方法で製造し得る。まず、乳酸カルシウム（５水
和物）を約2当量の濃塩酸と、同量の砕水の混合物の中
に加えて溶解し、濃厚な乳酸と塩化カルシウムの溶液を
調製する。この溶液中の乳酸を交流抽出塔の中でアルカ
ノールにより抽出する。得られた乳酸のブタノール溶液
を、分留塔を付した常圧での還流加熱により共沸する水
分を分離しつつ、エステル化を行う。この場合、アルカ
ノールとしては、1-ブタノールが好ましい。In the above process, the raw material lactate ester is
It can be manufactured by the following method. First, calcium lactate (pentahydrate) is added to a mixture of about 2 equivalents of concentrated hydrochloric acid and the same amount of crushed water and dissolved to prepare a solution of concentrated lactic acid and calcium chloride. Lactic acid in this solution is extracted with an alkanol in an AC extraction column. The resulting butanol solution of lactic acid is esterified while the azeotropic water is separated by heating under reflux at normal pressure equipped with a fractionating column. In this case, 1-butanol is preferable as the alkanol.
【００２５】[0025]
【実施例】以下、本発明を実施例および比較例を挙げて
説明する。EXAMPLES The present invention will be described below with reference to examples and comparative examples.
【００２６】（実施例１〜４、比較例１〜３）簡単な分
留管を付した蒸留装置に、500gのD,L-乳酸ブチルを仕込
み、表１に示す所定量の触媒を添加して、表１に示す反
応温度、反応時間で加熱した。水流ポンプで100mmHgに
減圧すると、生成したブタノールが約66℃で留出した。
ブタノールの留出速度が著しく遅くなってからさらに減
圧度を上げ、ブタノールを完全に留出させた後、昇温し
て乳酸ブチルを留出させた。高度真空ポンプに切り換
え、0.7mmHgの減圧にすると、43℃で乳酸ブチルが留出
した後、105℃でD,Lーラクチドが留出した。(Examples 1 to 4 and Comparative Examples 1 to 3) 500 g of D, L-butyl lactate was charged into a distillation apparatus equipped with a simple fractionating tube, and a predetermined amount of catalyst shown in Table 1 was added. Then, it was heated at the reaction temperature and reaction time shown in Table 1. When the pressure was reduced to 100 mmHg with a water-jet pump, the produced butanol was distilled at about 66 ° C.
After the distillation rate of butanol became extremely slow, the degree of vacuum was further increased to completely distill butanol, and then the temperature was raised to distill butyl lactate. When switching to a high vacuum pump and reducing the pressure to 0.7 mmHg, butyl lactate was distilled at 43 ° C, and then D, L-lactide was distilled at 105 ° C.
【００２７】得られたラクチドの収量および乳酸ブチル
の回収量を表１に示す。The yield of lactide and the recovered amount of butyl lactate obtained are shown in Table 1.
【００２８】[0028]
【表１】 [Table 1]
【００２９】（実施例５、比較例４）乳酸プレポリマー
200gに、表２に示す所定量の触媒を添加し、水流ポンプ
による約30mmHgの減圧下、180〜220℃で４時間加熱溶融
した。その後高度真空ポンプに切り換えて0.7mmHgの減
圧にし、92〜105℃で留出するラクチドを得た。得られ
たラクチドの収量、純度および融点を表２に示す。Example 5 and Comparative Example 4 Lactic acid prepolymer
A predetermined amount of the catalyst shown in Table 2 was added to 200 g, and the mixture was heated and melted at 180 to 220 ° C. for 4 hours under a reduced pressure of about 30 mmHg by a water jet pump. After that, the pressure was reduced to 0.7 mmHg by switching to a high vacuum pump to obtain lactide that distilled at 92 to 105 ° C. The yield, purity and melting point of the lactide obtained are shown in Table 2.
【００３０】[0030]
【表２】 [Table 2]
【００３１】本実施例の結果から、本発明のラクチド化
触媒を添加することにより、160℃の低い温度でもラク
チド化反応が速やかに進行し、また、得られたラクチド
の分解を抑えることができ、収量および純度が向上する
ことがわかる。From the results of this example, by adding the lactide-forming catalyst of the present invention, the lactide-forming reaction can proceed rapidly even at a low temperature of 160 ° C., and decomposition of the obtained lactide can be suppressed. It can be seen that the yield and the purity are improved.
【００３２】[0032]
【発明の効果】以上の説明で明らかなように、本発明の
ラクチド化触媒は、乳酸プレポリマーまたは乳酸エステ
ルからラクチドを製造する工程において、優れた触媒効
果を発揮することができる。本発明のラクチド化触媒を
使用すれば、多量の熱量を使用せず、かつ効率的にラク
チドの製造を行うことができ、さらには吸湿性の少ない
ラクチドを収量よく高純度で製造することができる。As is apparent from the above description, the lactide-forming catalyst of the present invention can exert an excellent catalytic effect in the step of producing lactide from a lactic acid prepolymer or a lactic acid ester. If the lactide-forming catalyst of the present invention is used, it is possible to efficiently produce lactide without using a large amount of heat, and further, it is possible to produce lactide with low hygroscopicity in high yield and high purity. .
Claims (3)
ラクチドを製造する工程で添加するラクチド化触媒であ
って、下記一般式〔I〕で表されるジブチル錫化合物で
ある、ラクチド化触媒。 【化１】 （式中、Ａ1およびＡ2は、それぞれ独立して、フッ素原
子、塩素原子、臭素原子、アセトキシ基、2-ヒドロキシ
プロピオニルオキシ基、メタンスルホニルオキシ基また
はトルエンスルホニルオキシ基を表すか、あるいは−Ａ
1および−Ａ2を併せて＝Ｏを表す）。1. A lactide-forming catalyst that is added in the step of producing lactide from a lactic acid prepolymer or a lactic acid ester and is a dibutyltin compound represented by the following general formula [I]. [Chemical 1] (In the formula, A 1 and A 2 each independently represent a fluorine atom, a chlorine atom, a bromine atom, an acetoxy group, a 2-hydroxypropionyloxy group, a methanesulfonyloxy group or a toluenesulfonyloxy group, or A
1 and -A 2 together represent = 0).
ラクチドを製造する工程で添加するラクチド化触媒であ
って、五酸化リンまたは三酸化リンである、ラクチド化
触媒。2. A lactide-forming catalyst that is added in the step of producing a lactide from a lactic acid prepolymer or a lactic acid ester and is phosphorus pentoxide or phosphorus trioxide.
ラクチドを製造する工程で添加するラクチド化触媒であ
って、請求項１の一般式〔I〕で表されるジブチル錫化
合物と、五酸化リンまたは三酸化リンとを組み合わせて
なる、ラクチド化触媒。3. A lactide-forming catalyst added in the step of producing a lactide from a lactic acid prepolymer or a lactic acid ester, which comprises a dibutyltin compound represented by the general formula [I] of claim 1 and phosphorus pentoxide or trioxide. A lactide-forming catalyst in combination with phosphorus oxide.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4187113A JPH0631175A (en) | 1992-07-14 | 1992-07-14 | Lactidation catalyst |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4187113A JPH0631175A (en) | 1992-07-14 | 1992-07-14 | Lactidation catalyst |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0631175A true JPH0631175A (en) | 1994-02-08 |
Family
ID=16200336
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4187113A Withdrawn JPH0631175A (en) | 1992-07-14 | 1992-07-14 | Lactidation catalyst |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0631175A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2264020A1 (en) | 2009-05-20 | 2010-12-22 | Korea Research Institute Of Chemical Technology | Catalyst for direct conversion of esters of lactic acid to lactide and the method for producing lactide using the same |
| JP2011506573A (en) * | 2007-12-19 | 2011-03-03 | フテロ ソシエテ アノニム | Method for producing lactide |
| KR101467202B1 (en) * | 2013-06-21 | 2014-12-01 | 한국화학연구원 | Shaped Catalyst For Direct Preparation of Lactide from Lactic Acid and Preparation of the Shaped Catalyst |
-
1992
- 1992-07-14 JP JP4187113A patent/JPH0631175A/en not_active Withdrawn
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011506573A (en) * | 2007-12-19 | 2011-03-03 | フテロ ソシエテ アノニム | Method for producing lactide |
| EP2264020A1 (en) | 2009-05-20 | 2010-12-22 | Korea Research Institute Of Chemical Technology | Catalyst for direct conversion of esters of lactic acid to lactide and the method for producing lactide using the same |
| US8258317B2 (en) | 2009-05-20 | 2012-09-04 | Korea Research Institute Of Chemical Technology | Catalyst for direct conversion of esters of lactic acid to lactide and the method for producing lactide using the same |
| KR101467202B1 (en) * | 2013-06-21 | 2014-12-01 | 한국화학연구원 | Shaped Catalyst For Direct Preparation of Lactide from Lactic Acid and Preparation of the Shaped Catalyst |
| WO2014204099A1 (en) * | 2013-06-21 | 2014-12-24 | 한국화학연구원 | Moulded catalyst for directly producing lactide from lactic acid, and production method for same |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A300 | Withdrawal of application because of no request for examination |
Free format text: JAPANESE INTERMEDIATE CODE: A300 Effective date: 19991005 |