JP3075607B2 - Lactide production method - Google Patents
Lactide production methodInfo
- Publication number
- JP3075607B2 JP3075607B2 JP03270781A JP27078191A JP3075607B2 JP 3075607 B2 JP3075607 B2 JP 3075607B2 JP 03270781 A JP03270781 A JP 03270781A JP 27078191 A JP27078191 A JP 27078191A JP 3075607 B2 JP3075607 B2 JP 3075607B2
- Authority
- JP
- Japan
- Prior art keywords
- lactide
- polylactic acid
- tin
- lactic acid
- heated
- 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.)
- Expired - Fee Related
Links
Landscapes
- Polyesters Or Polycarbonates (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は、新規な触媒を用いた乳
酸オリゴマーおよびラクチドの製造法に関する。The present invention relates to a method for producing lactic acid oligomers and lactides using a novel catalyst.
【０００２】[0002]
【従来の技術】独国特許明細書第２６７８２６号公報に
は、乳酸を２００℃の温度へ徐々に加熱し、生成するラ
クチドを好ましくは、減圧下で蒸留するラクチドの製造
法が記載されている。BACKGROUND OF THE INVENTION German Patent Specification No. 267826 describes a process for the production of lactide in which lactic acid is gradually heated to a temperature of 200 ° C. and the resulting lactide is distilled, preferably under reduced pressure. .
【０００３】独国特許明細書第１２３４７０３号公報に
は、チタンテトラアルコキシドの存在下での乳酸水溶液
からのラクチドの製造法が記載している。[0003] German Patent Specification No. 1234703 describes a process for the production of lactide from aqueous lactic acid in the presence of titanium tetraalkoxide.
【０００４】独国特許明細書第１０８３２７５号には、
周期表VI族、Ｖ族、または、VIII族の金属、または、そ
の塩、例えば、酸化亜鉛、酸化錫、酸化アンチモンの存
在下、ポリ乳酸からのラクチドの製造法が記載しされて
いる。[0004] German Patent Specification No. 1083275 describes:
A process for the production of lactide from polylactic acid in the presence of a Group VI, V, or VIII metal or a salt thereof, such as zinc oxide, tin oxide, antimony oxide, is described.
【０００５】特開昭６３−１０１３７８号公報には、金
属錫またはハロゲン化錫等の存在下、乳酸またはポリ乳
酸からのラクチドの製造法が記載されている。JP-A-63-101378 describes a method for producing lactide from lactic acid or polylactic acid in the presence of tin metal or tin halide.
【０００６】[0006]
【発明が解決しようとする課題】上記刊行物によるラク
チドの化学的収率は、決して満足できるものではない。
この中で、比較的ラクチド収率が良い特開昭６３−１０
１３７８号公報には、「９０％乳酸に触媒量の金属錫を
加え、この溶液を１５ｍｍＨｇの圧力下で約１７０℃ま
で水を留去しながら昇温しオリゴマ−へ転化させ、つい
で７．５ｍｍＨｇの圧力下で約２１５℃まで昇温しラク
チドを留出させる」ラクチドの製造法が記載されてい
る。この方法では、触媒として金属錫を用いているが、
これは、不均一触媒であるため触媒表面でのみ活性であ
るが、経済性を考慮し触媒の使用量を減らすためには、
反応中、均一になる触媒が望まれる。さらに、金属錫
は、２３２℃以上で溶融して塊状となり触媒の表面積が
著しく少なくなる欠点を有していた。また、ラクチド留
出の際は、留出する粗ラクチド中のラクチド純度を上げ
るために、一旦、オリゴマーを生成し、乳酸、鎖状二量
体、鎖状三量体等の留出を防ぐ必要がある。特開昭６３
−１０１３７８に記載された触媒の中で、このオリゴマ
ーの生成速度は、金属錫が速いが、その金属錫を用いて
も、ラクチド留出に十分な分子量のオリゴマーを得るの
に３〜４時間必要であった。The chemical yields of lactide according to the above publication are by no means satisfactory.
Among them, Japanese Patent Application Laid-Open No. 63-10 / 1988 has a relatively good lactide yield.
No. 1378 discloses that "a catalytic amount of metallic tin is added to 90% lactic acid, and the solution is heated to about 170 DEG C. under a pressure of 15 mmHg while distilling off water to convert the solution to an oligomer. The temperature is raised to about 215 ° C. under a pressure of about 215 ° C. to distill lactide ”. In this method, metal tin is used as a catalyst,
This is only active on the catalyst surface because it is a heterogeneous catalyst, but in order to reduce the amount of catalyst used in consideration of economy,
A catalyst that is homogeneous during the reaction is desired. Further, the metal tin has a disadvantage that it melts at 232 ° C. or higher to form a lump and the surface area of the catalyst is significantly reduced. In addition, in the case of lactide distillation, it is necessary to once generate oligomers and to prevent lactic acid, chain dimers, chain trimers, etc. from being distilled in order to increase the lactide purity in the crude lactide to be distilled. There is. JP 63
Among the catalysts described in US Pat. No. 101378, the rate of formation of this oligomer is high for metal tin, but it takes 3 to 4 hours to obtain an oligomer having a molecular weight sufficient for distilling lactide even when using metal tin. Met.
【０００７】本発明の目的は、オリゴマー生成速度が速
く、かつ、ラクチド収率が高い触媒を用いた経済性に優
れたラクチドの製造方法を提供することである。[0007] It is an object of the present invention to provide a process for producing lactide which is excellent in economic efficiency using a catalyst having a high oligomer formation rate and a high lactide yield.
【０００８】[0008]
【課題を解決するための手段】本発明者らは、鋭意検討
した結果、トリフルオロメタンスルホン酸錫（以下、Ｔ
ＦＳ錫と略す。）の存在下、乳酸を加熱すると、これま
で知られている触媒に比べ２倍以上の速度でオリゴマー
化が進みポリ乳酸が得られることを見出した。また、Ｔ
ＦＳ錫の存在下、ポリ乳酸を加熱すると高収率でラクチ
ドが留出されることを見出し、本発明を完成した。The inventors of the present invention have conducted intensive studies and as a result, have found that tin trifluoromethanesulfonate (hereinafter referred to as T
Abbreviated as FS tin. It has been found that when lactic acid is heated in the presence of (1), oligomerization proceeds at a rate twice or more higher than that of a conventionally known catalyst, and polylactic acid is obtained. Also, T
The inventors have found that lactide is distilled out in high yield when polylactic acid is heated in the presence of FS tin, and thus completed the present invention.
【０００９】すなわち本発明の第１の発明は、トリフル
オロメタンスルホン酸錫（ＴＦＳ錫）の存在下、乳酸を
加熱脱水することを特徴とするポリ乳酸の製造法であ
り、第２の発明は、トリフルオロメタンスルホン酸錫
（ＴＦＳ錫）の存在下、ポリ乳酸を加熱し、生成したラ
クチドを留出させることを特徴とするラクチドの製造法
であり、第３の発明は、触媒の存在下、または非存在下
に乳酸を加熱脱水し、一旦、ポリ乳酸を製造し、つい
で、トリフルオロメタンスルホン酸錫（ＴＦＳ錫）の存
在下、ポリ乳酸を加熱し、生成したラクチドを留出させ
ることを特徴とするラクチドの製造法である。That is, a first invention of the present invention is a method for producing polylactic acid, wherein lactic acid is heated and dehydrated in the presence of tin trifluoromethanesulfonate (TFS tin). A method for producing lactide, comprising heating polylactic acid in the presence of tin trifluoromethanesulfonate (TFS tin) to distill off the generated lactide. The third invention provides a method for producing lactide in the presence of a catalyst or Lactic acid is heated and dehydrated in the absence of lactic acid to produce polylactic acid once, and then the polylactic acid is heated in the presence of tin trifluoromethanesulfonate (TFS tin) to distill off the generated lactide. Is a method for producing lactide.
【００１０】第１の発明においてＴＦＳ錫を用いること
により、これまで知られている触媒に比べ２倍以上の速
度で乳酸のオリゴマー化が進み、平均分子量３００〜１
００００のより高い分子量のポリ乳酸が得られる。[0010] By using TFS tin in the first invention, the oligomerization of lactic acid proceeds more than twice as fast as the catalyst known so far, and the average molecular weight is 300-1.
A higher molecular weight polylactic acid of 0000 is obtained.
【００１１】ＴＦＳ錫を用いて乳酸からポリ乳酸を合成
する際に使用する乳酸は、Ｌ（＋）−乳酸、Ｄ（−）−
乳酸、または、その混合物を用いることができる。Lactic acid used for synthesizing polylactic acid from lactic acid using TFS tin is L (+)-lactic acid, D (-)-
Lactic acid or a mixture thereof can be used.
【００１２】ＴＦＳ錫を用いて乳酸からポリ乳酸を合成
する際の温度は、ＴＦＳ錫の分解が起こらず、脱水が容
易に進行する３００℃以下が良い。特に、減圧度とも関
係するが乳酸やラクチド等が留出しない温度である１０
０〜２００℃が好ましい。The temperature at the time of synthesizing polylactic acid from lactic acid using TFS tin is preferably 300 ° C. or less at which TFS tin does not decompose and dehydration proceeds easily. In particular, it is a temperature at which lactic acid, lactide and the like are not distilled, although it is related to the degree of pressure reduction.
0-200 ° C is preferred.
【００１３】ＴＦＳ錫を用いて乳酸からポリ乳酸を合成
する際の圧力は、脱水が効率的に進行する１〜１００ｍ
ｍＨｇが良い。好ましくは、反応温度とも関係するが、
乳酸やラクチドが留出しないよう１０〜５０ｍｍＨｇの
間で調整して行う。The pressure for synthesizing polylactic acid from lactic acid using TFS tin is 1 to 100 m at which dehydration proceeds efficiently.
mHg is good. Preferably, it is also related to the reaction temperature,
It adjusts between 10 and 50 mmHg so that lactic acid and lactide do not distill.
【００１４】使用するＴＦＳ錫の量は、乳酸の０．０１
〜５重量％以下で十分であり、特に経済的に０．０１〜
１重量％が好ましい。The amount of TFS tin used is 0.01% of lactic acid.
-5% by weight or less is sufficient,
1% by weight is preferred.
【００１５】第２の発明においてＴＦＳ錫を用いること
により、高収率で純度の高いラクチドを得ることができ
る。By using TFS tin in the second invention, lactide of high purity and high yield can be obtained.
【００１６】ＴＦＳ錫を用いてポリ乳酸からラクチドを
製造する際に使用するポリ乳酸は、作りやすさ、また
は、若干の加熱で液状になるという扱いやすさから平均
分子量３００以上が良く、特に、ラクチド留出分中への
乳酸あるいは乳酸の鎖状二量体の混入を防ぐということ
も考え合わせ、６００〜２０００が好ましい。The polylactic acid used when producing lactide from polylactic acid using TFS tin has an average molecular weight of 300 or more from the viewpoint of easiness of preparation or ease of handling that it becomes a liquid by a slight heating. Considering that lactic acid or a chain dimer of lactic acid is prevented from being mixed into the lactide distillate, 600 to 2,000 is preferable.
【００１７】このポリ乳酸は、Ｌ（＋）−乳酸、Ｄ
（−）−乳酸、または、その混合物を、触媒の非存在下
で加熱脱水することにより得られるものが使用できる。
また、周期表IV、Ｖ、VIII族の金属、あるいは、その塩
の存在下、Ｌ（＋）−乳酸、Ｄ（−）−乳酸、または、
その混合物を加熱脱水して得られるポリ乳酸を使用する
ことができる。もちろん、上記第１の発明で得られるポ
リ乳酸を使用することができる。This polylactic acid is composed of L (+)-lactic acid, D
(-)-Lactic acid or a mixture thereof obtained by heating and dehydrating in the absence of a catalyst can be used.
In addition, L (+)-lactic acid, D (-)-lactic acid or
Polylactic acid obtained by heating and dehydrating the mixture can be used. Of course, the polylactic acid obtained in the first invention can be used.
【００１８】ＴＦＳ錫を用いてポリ乳酸からラクチドを
製造する際の温度は、エステル交換反応に必要な温度以
上で、ＴＦＳ錫の分解温度以下、即ち、１３０〜３００
℃が良く、特に、１７０〜２５０℃が好ましい。The temperature for producing lactide from polylactic acid using TFS tin is higher than the temperature required for transesterification and lower than the decomposition temperature of TFS tin, ie, 130 to 300.
C is good, and particularly preferably 170 to 250C.
【００１９】ＴＦＳ錫を用いてポリ乳酸からラクチドを
製造する際の圧力は、上記温度範囲でラクチドが効率良
く留出する圧力、すなわち、１００ｍｍＨｇ以下が良
く、特に１〜１０ｍｍＨｇが好ましい。温度と圧力は相
互に関連し、上記温度範囲でラクチドが留出している
際、乳酸の鎖状二量体、鎖状三量体等が留出しないよう
圧力が調整される。The pressure at which lactide is produced from polylactic acid using TFS tin is preferably a pressure at which lactide is efficiently distilled in the above temperature range, that is, 100 mmHg or less, and particularly preferably 1 to 10 mmHg. The temperature and the pressure are related to each other, and the pressure is adjusted so that, when lactide is distilled out in the above temperature range, a chain dimer, a chain trimer and the like of lactic acid do not distill.
【００２０】ポリ乳酸からラクチドを製造する際の使用
するＴＦＳ錫の量は、ポリ乳酸の０．０１〜５重量％以
下で十分であり、これ以上使用することは経済的に不利
である。好ましくは０．０１〜１重量％が良い。The amount of TFS tin used in the production of lactide from polylactic acid is sufficient if it is 0.01 to 5% by weight or less of polylactic acid, and using more than this is economically disadvantageous. Preferably, the content is 0.01 to 1% by weight.
【００２１】なお、ＴＦＳ錫は、Inorganic Chemistry,
16,1414(1977) 記載の方法により製造することができ
る。TFS tin is available from Inorganic Chemistry,
16, 1414 (1977).
【００２２】以上の乳酸からポリ乳酸を製造する工程、
および、ポリ乳酸からラクチドを製造する工程を連結し
て連続的に行うことができ、その時の反応条件はそれぞ
れ上記の条件を用いることができる。すなわち、触媒の
存在下、または非存在下、乳酸を加熱脱水し、一旦ポリ
乳酸を製造し、つづいてＴＦＳ錫の存在下、得られたポ
リ乳酸を減圧下加熱しラクチドを留出させる。A step of producing polylactic acid from the above lactic acid;
In addition, the steps for producing lactide from polylactic acid can be continuously performed by connecting the steps, and the reaction conditions at that time can be the same as those described above. That is, lactic acid is heated and dehydrated in the presence or absence of a catalyst to produce polylactic acid once, and then, in the presence of TFS tin, the obtained polylactic acid is heated under reduced pressure to distill lactide.
【００２３】[0023]
【実施例】以下、実施例で本発明を説明する。EXAMPLES The present invention will be described below with reference to examples.
【００２４】実施例１ ＴＦＳ錫０．３６ｇを９０％Ｌ−乳酸１００ｇに添加
し、２００℃，３０ｍｍＨｇで３時間攪拌後、２００
℃，１０ｍｍＨｇで約１時間加熱攪拌し、５１．０ｇの
平均分子量７０００であるポリ乳酸を得た。Example 1 0.36 g of TFS tin was added to 100 g of 90% L-lactic acid, and the mixture was stirred at 200 ° C. and 30 mmHg for 3 hours.
The mixture was heated and stirred at 10 mmHg for about 1 hour to obtain 51.0 g of polylactic acid having an average molecular weight of 7,000.
【００２５】比較例１ 実施例１のＴＦＳ錫の代わりに金属錫を用いた以外は、
実施例１と同様に反応し、処理した。４５．０ｇの平均
分子量３０００であるポリ乳酸を得た。Comparative Example 1 Except for using metal tin instead of TFS tin in Example 1,
The reaction and treatment were carried out in the same manner as in Example 1. 45.0 g of polylactic acid having an average molecular weight of 3000 was obtained.
【００２６】実施例２ ＴＦＳ錫２．２６ｇを平均分子量４６０のＬ（−）−ポ
リ乳酸６３４ｇへ添加し、１５０℃，３０ｍｍＨｇで１
時間攪拌した。その結果、ポリ乳酸の平均分子量は、８
００〜８５０に増加した。その後、５ｍｍＨｇに減圧
し、１７５〜２３０℃でラクチドを留出させ６０９ｇの
粗ラクチドを得た。これを３００ｇのイソプロピルアル
コールで２回洗浄し、乾燥後、５０５ｇの純粋なラクチ
ドを得た。 収率８３％（ポリ乳酸中の乳酸ユニットの総数に対する
得られたラクチド中の乳酸ユニットの総数） 融点 ９６〜９８℃Example 2 2.26 g of TFS tin was added to 634 g of L (−)-polylactic acid having an average molecular weight of 460, and the mixture was added at 150 ° C. and 30 mmHg to obtain a solution.
Stirred for hours. As a result, the average molecular weight of polylactic acid was 8
It increased to 00-850. Thereafter, the pressure was reduced to 5 mmHg, and lactide was distilled at 175 to 230 ° C to obtain 609 g of crude lactide. This was washed twice with 300 g of isopropyl alcohol, and after drying, 505 g of pure lactide was obtained. Yield 83% (total number of lactic acid units in lactide obtained relative to total number of lactic acid units in polylactic acid) Melting point 96-98 ° C
【００２７】比較例２ 実施例２のＴＦＳ錫の代わりに金属錫を用いた以外は、
実施例１と同様に反応し、処理した。６０２ｇの粗ラク
チドが得られ、これを実施例２と同様に精製し、４３９
ｇの純粋なラクチドを得た。 収率７３％（ポリ乳酸中の乳酸ユニットの総数に対する
得られたラクチド中の乳酸ユニットの総数） 融点 ９６〜９８℃Comparative Example 2 Except for using metal tin instead of TFS tin in Example 2,
The reaction and treatment were carried out in the same manner as in Example 1. 602 g of crude lactide were obtained, which was purified as in Example 2 and
g of pure lactide were obtained. Yield 73% (total number of lactic acid units in lactide obtained relative to total number of lactic acid units in polylactic acid) Melting point 96-98 ° C
【００２８】実施例３ ＴＦＳ錫１．９６ｇを平均分子量５５０のＬ（−）−ポ
リ乳酸６５２ｇへ添加し、１５０℃，３０ｍｍＨｇで１
時間攪拌した。その結果、ポリ乳酸の平均分子量は、８
００〜８５０に増加した。その後、５ｍｍＨｇに減圧
し、１７５〜２３０℃でラクチドを留出させ６３６ｇの
粗ラクチドを得た。反応機に釜残として１１ｇの残渣が
残った。これに新たに前記のポリ乳酸７１３ｇを加え、
同様に処理し、７０３ｇの粗ラクチドを得た。反応機に
釜残として１３ｇの残渣が残った。同様にさらに二度そ
れぞれ７３５ｇ、６１３ｇの前記のポリ乳酸を加え、同
様に処理した。粗ラクチドそれぞれ７１２ｇ、６００ｇ
を得た。４回の処理で得られた粗ラクチドを合わせて２
６５１ｇを、１２５０ｇのイソプロピルアルコールで２
回洗浄し、乾燥後、２２３５ｇの純粋なラクチドを得
た。 収率８５％（ポリ乳酸中の乳酸ユニットの総数に対する
得られたラクチド中の乳酸ユニットの総数） 融点 ９６〜９８℃Example 3 1.96 g of TFS tin was added to 652 g of L (-)-polylactic acid having an average molecular weight of 550, and the solution was added at 150 ° C. and 30 mmHg to obtain a solution of 1%.
Stirred for hours. As a result, the average molecular weight of polylactic acid was 8
It increased to 00-850. Thereafter, the pressure was reduced to 5 mmHg, and lactide was distilled at 175 to 230 ° C to obtain 636 g of crude lactide. 11 g of residue remained in the reactor as a kettle residue. 713 g of the above-mentioned polylactic acid is newly added to this,
The same treatment was performed to obtain 703 g of crude lactide. 13 g of residue remained in the reactor as a kettle residue. Similarly, 735 g and 613 g of the above-mentioned polylactic acid were further added twice and treated in the same manner. 712 g, 600 g of crude lactide
I got The crude lactide obtained by the four treatments is combined into 2
651 g with 1250 g of isopropyl alcohol
After washing twice and drying, 2235 g of pure lactide were obtained. Yield 85% (total number of lactic acid units in lactide obtained relative to total number of lactic acid units in polylactic acid) Melting point 96-98 ° C
【００２９】実施例４ ＴＦＳ錫１．９８ｇを９０％Ｌ−乳酸６００ｇへ添加
し、１５ｍｍＨｇの圧力下で１７０℃まで水を留去しな
がら昇温する。その後、１７０℃、１５ｍｍＨｇで約１
時間加熱攪拌し、分子量８４０の中分子量のポリ乳酸を
生成した。この際、ＴＦＳ錫は、均一に溶解する。これ
を、さらに７．５ｍｍＨｇに減圧し、１７５〜２２０℃
で生成したラクチドを留出させ、４０２ｇの粗ラクチド
を得た。これを１９０ｇのイソプロピルアルコールで２
回洗浄し、乾燥後、３２９ｇの純粋なラクチドを得た。 収率７６％（Ｌ−乳酸に対するラクチドの収率） 融点 ９６〜９８℃Example 4 1.98 g of TFS tin was added to 600 g of 90% L-lactic acid, and the temperature was raised to 170 ° C. under a pressure of 15 mmHg while distilling off water. Thereafter, at 170 ° C. and 15 mmHg for about 1
The mixture was heated and stirred for a period of time to produce polylactic acid having a medium molecular weight of 840. At this time, TFS tin dissolves uniformly. The pressure was further reduced to 7.5 mmHg,
The lactide produced in was distilled off to obtain 402 g of crude lactide. This is mixed with 190 g of isopropyl alcohol for 2
After washing twice and drying, 329 g of pure lactide were obtained. Yield 76% (Yield of lactide based on L-lactic acid) Melting point 96-98 ° C
【００３０】比較例３ 金属錫１．９８ｇを９０％Ｌ−乳酸６００ｇへ添加し、
１５ｍｍＨｇの圧力下で１７０℃まで水を留去しながら
昇温する。その後、１７０℃、１５ｍｍＨｇで約３時間
加熱攪拌し、分子量８２０の中分子量のポリ乳酸を生成
した。これを、さらに７．５ｍｍＨｇに減圧し、１７５
〜２２０℃で生成したラクチドを留出させ、３７０ｇの
粗ラクチドを得た。これを１７５ｇのイソプロピルアル
コールで２回洗浄し、乾燥後、２８９ｇの純粋なラクチ
ドを得た。 収率６７％（Ｌ−乳酸に対するラクチドの収率） 融点 ９６〜９８℃Comparative Example 3 1.98 g of metal tin was added to 600 g of 90% L-lactic acid.
The temperature is raised to 170 ° C. while distilling off water under a pressure of 15 mmHg. Thereafter, the mixture was heated and stirred at 170 ° C. and 15 mmHg for about 3 hours to produce polylactic acid having a molecular weight of 820 and a medium molecular weight. The pressure was further reduced to 7.5 mmHg, and 175
The lactide produced was distilled at ℃ 220 ° C. to obtain 370 g of crude lactide. This was washed twice with 175 g of isopropyl alcohol and dried to obtain 289 g of pure lactide. Yield 67% (Yield of lactide based on L-lactic acid) Melting point 96-98 ° C
フロントページの続き (58)調査した分野(Int.Cl.7，ＤＢ名) C08G 63/08 C08G 63/85 ＣＡ（ＳＴＮ) ＲＥＧＩＳＴＲＹ（ＳＴＮ)Continued on the front page (58) Fields surveyed (Int. Cl. 7 , DB name) C08G 63/08 C08G 63/85 CA (STN) REGISTRY (STN)
Claims (5)
下、乳酸を加熱脱水することを特徴とするポリ乳酸の製
造法。1. A method for producing polylactic acid, comprising heating and dehydrating lactic acid in the presence of tin trifluoromethanesulfonate.
下、ポリ乳酸を加熱し生成したラクチドを留出させるこ
とを特徴とするラクチドの製造法。2. A process for producing lactide, comprising heating polylactic acid in the presence of tin trifluoromethanesulfonate to distill lactide formed.
る請求項２記載のラクチドの製造法。3. The method for producing lactide according to claim 2, wherein the average molecular weight of the polylactic acid is 300 or more.
加熱脱水し、一旦、ポリ乳酸を製造し、ついで、トリフ
ルオロメタンスルホン酸錫の存在下、ポリ乳酸を加熱
し、生成したラクチドを留出させることを特徴とするラ
クチドの製造法。4. Lactic acid is heated and dehydrated in the presence or absence of a catalyst to produce polylactic acid, and then the polylactic acid is heated in the presence of tin trifluoromethanesulfonate to produce lactide. A process for producing lactide, characterized by distilling.
下に乳酸を加熱脱水し、一旦、ポリ乳酸を製造し、つい
で、トリフルオロメタンスルホン酸錫の存在下、ポリ乳
酸を加熱し、生成したラクチドを留出させることを特徴
とするラクチドの製造法。5. Lactic acid is heated and dehydrated in the presence of tin trifluoromethanesulfonate to once produce polylactic acid, and then polylactic acid is heated in the presence of tin trifluoromethanesulfonate to distill the lactide produced. A method for producing lactide, characterized in that the lactide is produced.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP03270781A JP3075607B2 (en) | 1991-10-18 | 1991-10-18 | Lactide production method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP03270781A JP3075607B2 (en) | 1991-10-18 | 1991-10-18 | Lactide production method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05105745A JPH05105745A (en) | 1993-04-27 |
| JP3075607B2 true JP3075607B2 (en) | 2000-08-14 |
Family
ID=17490910
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP03270781A Expired - Fee Related JP3075607B2 (en) | 1991-10-18 | 1991-10-18 | Lactide production method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3075607B2 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2028209B1 (en) * | 2006-06-15 | 2014-08-13 | National University Corporation Kyoto Institute of Technology | Method for producing poly-L-lactic acid |
| EP2072508A1 (en) * | 2007-12-19 | 2009-06-24 | Galactic S.A. | Method for obtaining lactide |
| WO2009142196A1 (en) * | 2008-05-21 | 2009-11-26 | 東レ株式会社 | Method for producing aliphatic polyester resin, and an aliphatic polyester resin composition |
| CN115232102B (en) * | 2022-09-06 | 2024-02-13 | 中国科学院长春应用化学研究所 | Preparation method and production device of lactide |
-
1991
- 1991-10-18 JP JP03270781A patent/JP3075607B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH05105745A (en) | 1993-04-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5053522A (en) | Process for the preparation of lactide | |
| JPS63101378A (en) | Manufacture of lactide | |
| US4163860A (en) | Process for obtaining dimethyl terephthalate from polyester scrap | |
| JP5179595B2 (en) | Method for producing lactide | |
| US8258317B2 (en) | Catalyst for direct conversion of esters of lactic acid to lactide and the method for producing lactide using the same | |
| JPH07165753A (en) | Purification of lactide | |
| JPH09505323A (en) | Polylactic acid production method | |
| JP3075607B2 (en) | Lactide production method | |
| US5430174A (en) | Method for recovering dimethyl naphthalene-2,6-dicarboxylate | |
| US4365088A (en) | Process for the manufacture of β-hydroxybutyric acid and its oligocondensates | |
| CN114149324A (en) | Synthesis method of 6-hydroxy-8-chloro ethyl caprylate, 6, 8-dichloro ethyl caprylate and lipoic acid | |
| JPH07138343A (en) | Production of polyisocyanate containing isocyanurate and/or uretedione groups and having lowered color index and improved storage life and product produced thereby | |
| EP2539332B1 (en) | Improved process for the preparation of l-lactide of high chemical yield and optical purity | |
| CN113845508B (en) | Method for preparing lactide by using bimetallic composite catalyst | |
| US5266706A (en) | Solvent scrubbing recovery of lactide and other dimeric cyclic esters | |
| JPS6239157B2 (en) | ||
| KR101183982B1 (en) | Process for preparing lactide and polylactide from Lactic acid fermentation | |
| KR101327892B1 (en) | Method for preparing lactide from alkyl lactate | |
| JP2863269B2 (en) | Method for producing cyclic lactone | |
| JPS6331403B2 (en) | ||
| JP3409441B2 (en) | Method for producing aliphatic polyester | |
| JPH0631175A (en) | Lactidation catalyst | |
| JP3001098B1 (en) | Method for producing sorbic acid | |
| JPH09110860A (en) | Production of lactide | |
| JP3073922B2 (en) | Method for producing lactic acid polymer |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |