JPH01168730A - Purification of polycarbonate - Google Patents
Purification of polycarbonateInfo
- Publication number
- JPH01168730A JPH01168730A JP32677987A JP32677987A JPH01168730A JP H01168730 A JPH01168730 A JP H01168730A JP 32677987 A JP32677987 A JP 32677987A JP 32677987 A JP32677987 A JP 32677987A JP H01168730 A JPH01168730 A JP H01168730A
- Authority
- JP
- Japan
- Prior art keywords
- polycarbonate
- methylene chloride
- fluid
- impurities
- state
- 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.)
- Granted
Links
- 229920000515 polycarbonate Polymers 0.000 title claims abstract description 35
- 239000004417 polycarbonate Substances 0.000 title claims abstract description 35
- 238000000746 purification Methods 0.000 title claims abstract description 7
- YMWUJEATGCHHMB-UHFFFAOYSA-N Dichloromethane Chemical compound ClCCl YMWUJEATGCHHMB-UHFFFAOYSA-N 0.000 claims abstract description 42
- 239000012535 impurity Substances 0.000 claims abstract description 17
- 239000012530 fluid Substances 0.000 claims abstract description 16
- 238000000034 method Methods 0.000 claims description 31
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical group O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims description 25
- 229910002092 carbon dioxide Inorganic materials 0.000 claims description 12
- 239000001569 carbon dioxide Substances 0.000 claims description 11
- 238000000605 extraction Methods 0.000 abstract description 11
- 238000011282 treatment Methods 0.000 abstract description 6
- YGYAWVDWMABLBF-UHFFFAOYSA-N Phosgene Chemical compound ClC(Cl)=O YGYAWVDWMABLBF-UHFFFAOYSA-N 0.000 abstract description 5
- VPWNQTHUCYMVMZ-UHFFFAOYSA-N 4,4'-sulfonyldiphenol Chemical class C1=CC(O)=CC=C1S(=O)(=O)C1=CC=C(O)C=C1 VPWNQTHUCYMVMZ-UHFFFAOYSA-N 0.000 abstract description 4
- 229930185605 Bisphenol Natural products 0.000 abstract description 4
- 239000002904 solvent Substances 0.000 abstract description 4
- 238000012696 Interfacial polycondensation Methods 0.000 abstract description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 7
- JUJWROOIHBZHMG-UHFFFAOYSA-N Pyridine Chemical compound C1=CC=NC=C1 JUJWROOIHBZHMG-UHFFFAOYSA-N 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 4
- 229910052757 nitrogen Inorganic materials 0.000 description 3
- IISBACLAFKSPIT-UHFFFAOYSA-N bisphenol A Chemical compound C=1C=C(O)C=CC=1C(C)(C)C1=CC=C(O)C=C1 IISBACLAFKSPIT-UHFFFAOYSA-N 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 239000008187 granular material Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- UMJSCPRVCHMLSP-UHFFFAOYSA-N pyridine Natural products COC1=CC=CN=C1 UMJSCPRVCHMLSP-UHFFFAOYSA-N 0.000 description 2
- 238000005809 transesterification reaction Methods 0.000 description 2
- OTMSDBZUPAUEDD-UHFFFAOYSA-N Ethane Chemical compound CC OTMSDBZUPAUEDD-UHFFFAOYSA-N 0.000 description 1
- 238000012695 Interfacial polymerization Methods 0.000 description 1
- 229910002090 carbon oxide Inorganic materials 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 238000011437 continuous method Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000006837 decompression Effects 0.000 description 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- -1 etc. Chemical compound 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000004817 gas chromatography Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000011866 long-term treatment Methods 0.000 description 1
- 239000012046 mixed solvent Substances 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 239000008188 pellet Substances 0.000 description 1
- 238000006116 polymerization reaction Methods 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明はポリカーボネートの精製方法に関し、詳しくは
不純物を含有するポリカーボネートを、亜臨界状態乃至
超臨界状態に設定した流体を用いて抽出処理することに
より、効率よく精製して高純度のポリカーボネートを得
る方法に関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for purifying polycarbonate, and more specifically, a method for extracting polycarbonate containing impurities using a fluid set in a subcritical or supercritical state. This invention relates to a method for efficiently purifying and obtaining highly pure polycarbonate.
〔従来の技術及び発明が解決しようとする問題点〕従来
、塩化メチレン等の溶媒を用いて製造したポリカーボネ
ートから、８亥ポリカーボネートに混入した塩化メチレ
ン等の不純物を除去（乾燥）するには、減圧下あるいは
窒素気流下でパドル乾燥機や流動乾燥機等を用いて行わ
れていた。また、そのほかに水蒸気を熱媒として使用す
る方法も知られている（特開昭５４−１０１７７１号公
報）。[Prior art and problems to be solved by the invention] Conventionally, in order to remove (dry) impurities such as methylene chloride mixed into polycarbonate from polycarbonate produced using a solvent such as methylene chloride, reduced pressure is used. This was done using a paddle dryer, fluidized bed dryer, etc. under a nitrogen stream or under a stream of nitrogen. In addition, a method using steam as a heating medium is also known (Japanese Patent Laid-Open No. 101771/1983).
しかしながらこれらの方法は、いずれも塩化メチレン等
の混入溶媒の乾燥度を上昇させるために、１００℃以上
の比較的高温下で長時間処理することが必要であり、効
率のよい方法とは言い難いものであった。However, all of these methods require long-term treatment at a relatively high temperature of 100°C or higher in order to increase the degree of dryness of the mixed solvent such as methylene chloride, so they cannot be called efficient methods. It was something.
そこで、本発明者らは、上記従来の方法の問題点を解消
し、ポリカーボネートの製造工程において、ポリカーボ
ネートの乾燥時間をできるだけ短縮して、不純物として
の塩化メチレン等を効率よく除去することのできる方法
を開発すべく鋭意研究を重ねた。Therefore, the present inventors have developed a method that solves the problems of the conventional methods described above, shortens the drying time of polycarbonate as much as possible in the polycarbonate manufacturing process, and efficiently removes methylene chloride and the like as impurities. We conducted extensive research to develop this.
〔問題点を解決するための手段］
その結果、乾燥媒体（抽出媒体）として、超臨界状態ま
たは臨界状態近傍の流体を用いることによって、上記目
的が達成できることを見出した。[Means for Solving the Problems] As a result, it has been found that the above object can be achieved by using a fluid in a supercritical state or near a critical state as a drying medium (extraction medium).
本発明はかかる知見に基いて完成したものである。The present invention was completed based on this knowledge.
すなわち本発明は、不純物を含有する粉末状ポリカーボ
ネートを、亜臨界状態乃至超臨界状態の流体を用いて抽
出処理することを特徴とするポリカーボネートの精製方
法を提供するものである。That is, the present invention provides a polycarbonate purification method characterized by extracting powdered polycarbonate containing impurities using a fluid in a subcritical or supercritical state.
本発明の方法を適用する粉末状ポリカーボネートには、
各種の不純物が含まれているが、本発明の方法によれば
塩化メチレン、未反応ビスフェノール類など、分子量が
１０００以下のものを特に好ましく除去することができ
る。また、この不純物を含有する粉末状ポリカーボネー
トは、様々な方法によって得られたものがあるが、通常
はホスゲン法、特にビスフェノールＡ等のビスフェノー
ル類とホスゲンを原料とし、塩化メチレンを溶媒とする
界面重縮合法、とりわけ連続界面重縮合法によって製造
された分子量１００００〜５００００のものが好適に用
いられる。そのほか、エステル交換法やホスゲン法のう
ちのピリジンを溶媒とする所謂ピリジン重合法によって
得られたものを用いることもできる。The powdered polycarbonate to which the method of the present invention is applied includes:
Although various impurities are contained, according to the method of the present invention, those having a molecular weight of 1000 or less, such as methylene chloride and unreacted bisphenols, can be particularly preferably removed. Powdered polycarbonate containing this impurity can be obtained by various methods, but it is usually the phosgene method, especially the interfacial polymerization method using bisphenols such as bisphenol A and phosgene as raw materials and methylene chloride as a solvent. Those having a molecular weight of 10,000 to 50,000 produced by a condensation method, especially a continuous interfacial polycondensation method are preferably used. In addition, those obtained by the so-called pyridine polymerization method using pyridine as a solvent among the transesterification method and the phosgene method can also be used.
上記の粉末状ポリカーボネートとは、厳密な意味での粉
末状のものに限定するわけではなく、フレーク状等のも
のをも包含する。つまり、ホスゲン法やエステル交換法
で得られた粉末状５粒状。The above-mentioned powdery polycarbonate is not limited to powdery polycarbonate in a strict sense, but also includes flaky polycarbonate and the like. In other words, 5 grains of powder obtained by the phosgene method or transesterification method.
フレーク状等のポリカーボネートであって、ベレット化
する前のものすべてを包含した概念である。This concept includes all types of polycarbonate in the form of flakes, etc., before being made into pellets.
たとえば、上述の連続界面重縮合により得られる粉末状
ポリカーボネートは、通常はフレーク状であって、不純
物として塩化メチレンを最高３０重量％程度まで含み、
また未反応ビスフェノール類をｌＯ〜２００ ｐｐｍ、
低分子量成分（ポリカーボネートオリゴマー等）を４〜
８重量重量％台有している。For example, the powdered polycarbonate obtained by the above-mentioned continuous interfacial polycondensation is usually in the form of flakes and contains up to about 30% by weight of methylene chloride as an impurity.
In addition, unreacted bisphenols were added to lO~200 ppm,
4 to 4 low molecular weight components (polycarbonate oligomers, etc.)
It has a content of 8% by weight.
本発明の方法では、上記の不純物を含有する粉末状ポリ
カーボネートを、抽出処理して該ポリカーボネート中の
不純物を除去するが、この抽出処理には、亜臨界状態乃
至超臨界状態の流体を用いることが必要である。ここで
使用できる流体としては、各種のものがあげられるが、
具体的には二酸化炭素、−酸化炭素、メタン、窒素、エ
タン等があり、特に二酸化炭素が、不活性かつ無害であ
って、しかモ臨界条件が温和であることから好ましく使
用することができる。In the method of the present invention, the powdered polycarbonate containing the impurities described above is extracted to remove the impurities in the polycarbonate, and a fluid in a subcritical or supercritical state may be used for this extraction process. is necessary. There are various types of fluids that can be used here, but
Specifically, there are carbon dioxide, carbon oxide, methane, nitrogen, ethane, etc., and carbon dioxide is particularly preferably used because it is inert and harmless, and has mild critical conditions.
本発明の方法では、これらの流体を亜臨界状態乃至超臨
界状態にて使用する。ここで亜臨界状態とは、臨界状態
には達していないが、それに極めて近い状態を意味し、
また超臨界状態とは、臨界温度及び臨界圧力を超えた温
度及び圧力の状態を意味する。本発明の方法では、流体
を臨界状態あるいはその前後、即ち亜臨界状態から超臨
界状態までの間の条件下で使用する。In the method of the present invention, these fluids are used in a subcritical to supercritical state. Here, subcritical state means a state that has not reached the critical state but is very close to it.
Moreover, a supercritical state means a state of temperature and pressure exceeding critical temperature and critical pressure. In the method of the present invention, the fluid is used under conditions at or around a critical state, that is, between a subcritical state and a supercritical state.
具体的な条件としては、用いる流体の種類により異なり
一義的に定められないが、一般に圧力７０〜５００ｋｇ
／ｃＪ、温度３０〜３００℃の範囲で定めればよい。例
えば流体として二酸化炭素を用いる場合には、使用圧力
をＰ、使用温度をＴ。Specific conditions vary depending on the type of fluid used and cannot be unambiguously determined, but generally the pressure is 70 to 500 kg.
/cJ and the temperature may be set within the range of 30 to 300°C. For example, when carbon dioxide is used as the fluid, the working pressure is P and the working temperature is T.
二酸化炭素の臨界圧力をＰｃ （７２，８ｋｇ／ｃｄ）
。The critical pressure of carbon dioxide is Pc (72.8kg/cd)
.
二酸化炭素の臨界温度をＴｃ（３１，０″Ｃ）としたと
きに、０．９Ｐ、≦Ｐ≦１０Ｐｃであるとともに、０．
９ＴＣ≦Ｔ≦３００℃の範囲で選定することが好ましい
。When the critical temperature of carbon dioxide is Tc (31,0″C), 0.9P, ≦P≦10Pc, and 0.9P≦P≦10Pc.
It is preferable to select within the range of 9TC≦T≦300°C.
また、亜臨界状態乃至超臨界状態で上記流体を用いて、
粉末状ポリカーボネートを抽出処理するにあたっては、
様々な手法によることができるが、例えば抽出槽に処理
すべき粉末状ポリカーボネートを充填しておき、これに
亜臨界状態乃至超臨界状態の流体を連続的に流す方法が
効果的であるとともに、操作が容易であり好ましい。こ
のときの流体の流量は、各種状況により適宜選定すれば
よいが、好ましくは粉末状ポリカーボネート１ｇあたり
、分速０．０１〜２０戚、更に好ましくは０．１〜１０
ｍ１とする。あるいはこのような連続式に代えて、バッ
チ式によっても行うことができる。In addition, using the above fluid in a subcritical state or a supercritical state,
When extracting powdered polycarbonate,
Various methods can be used, but for example, it is effective to fill an extraction tank with powdered polycarbonate to be treated and to continuously flow a fluid in a subcritical or supercritical state through it. is easy and preferable. The flow rate of the fluid at this time may be appropriately selected depending on various situations, but preferably 0.01 to 20 per minute, more preferably 0.1 to 10 per gram of powdered polycarbonate.
Let it be m1. Alternatively, instead of such a continuous method, a batch method can also be used.
次に、本発明を実施例及び比較例により更に詳しく説明
する。Next, the present invention will be explained in more detail with reference to Examples and Comparative Examples.
実施例１
２０ｄステンレス製セルに、平均粒径０．５鵬のポリカ
ーボネート粒状体（不純物としての塩化メチレンを２．
０ｗｔ％含有する。）を約４００■入れ、１ｍ１／分（
液換算）の速度で、５０℃１１００ｋｇ／ｄの二酸化炭
素（超臨界状態ＣＯりを２時間供給し続けた。Example 1 Polycarbonate granules with an average particle size of 0.5 mm (2.0 mm of methylene chloride as an impurity were added to a 20 d stainless steel cell).
Contains 0wt%. ), and put about 400 ■ 1m1/min (
1100 kg/d of carbon dioxide (supercritical CO2) was continuously supplied at 50° C. for 2 hours at a rate of 1,100 kg/d (in terms of liquid).
抽出処理後、得られた精製ポリカーボネート中の不純物
である塩化メチレンを、ガスクロマトグラフィーにより
測定した。結果を表に示す。After the extraction treatment, methylene chloride, an impurity, in the obtained purified polycarbonate was measured by gas chromatography. The results are shown in the table.
実施例２
実施例１において、不純物としての塩化メチレンを１０
−ｔ％含有する平均粒径０．５ｍｍのポリカーボネート
粒状体を用い、７０°ｃ、２００ｋｇ／ｃＪの二酸化炭
素（超臨界状態ＣＯ□）を流し続けた以外は、実施例１
と同様にして抽出処理した。結果を表に示す。Example 2 In Example 1, methylene chloride as an impurity was added to 10
Example 1 except that polycarbonate granules containing -t% and an average particle size of 0.5 mm were used, and 200 kg/cJ of carbon dioxide (supercritical state CO□) was continued to flow at 70°C.
The extraction process was carried out in the same manner. The results are shown in the table.
比較例１
実施例１において、１０００＋ｌ／分（ガス換算）の速
度で７０℃２常圧の二酸化炭素を流し続けた以外は、実
施例１と同様にして抽出処理した。結果を表に示す。Comparative Example 1 Extraction treatment was carried out in the same manner as in Example 1, except that carbon dioxide at 70°C and 2 normal pressures was continued to flow at a rate of 1000+l/min (gas equivalent). The results are shown in the table.
比較例２
実施４Ｉｆｉ口において、二酸化炭素の代わりに、１２
０℃１常圧の窒素ガスを流量１０００ｄ／分で流し続け
た以外は、実施例１と同様にして抽出処理した。結果を
表に示す。Comparative Example 2 Execution 4 At the Ifi port, instead of carbon dioxide, 12
Extraction treatment was carried out in the same manner as in Example 1, except that nitrogen gas at 0° C. and 1 normal pressure was continued to flow at a flow rate of 1000 d/min. The results are shown in the table.
比較例３
実施例１において、二酸化炭素を流す代わりに、１２０
℃の雰囲気下、５ａｎＨｇ以下の真空度にて、２時間減
圧処理を行った。結果を表に示す。Comparative Example 3 In Example 1, instead of flowing carbon dioxide, 120
Decompression treatment was performed for 2 hours at a vacuum degree of 5 anHg or less in an atmosphere of .degree. The results are shown in the table.
実施例３
実施例２において、温度を７０℃から１５０℃に変え、
また圧力を２００ ｋｇ／ｃＪから３００ｋｇ／ＣＩＩ
Ｉに変えた以外は、実施例２と同様にして抽出処理した
。結果を表に示す。Example 3 In Example 2, the temperature was changed from 70°C to 150°C,
Also, increase the pressure from 200 kg/cJ to 300 kg/CII
The extraction process was carried out in the same manner as in Example 2, except that the extract was changed to I. The results are shown in the table.
実施例４
実施例１において、温度を５０℃から１００℃に変え、
また圧力を１００ｋｇ／ｃｉｌｌから２００ｋｇ／ｃ＋
ｆｉに変えた以外は、実施例１と同様にして抽出処理し
た。結果を表に示す。Example 4 In Example 1, the temperature was changed from 50°C to 100°C,
Also, the pressure can be changed from 100kg/cil to 200kg/c+
Extraction processing was carried out in the same manner as in Example 1 except that fi was used. The results are shown in the table.
実施例５
実施例１において、温度を５０℃から４０℃に変え、ま
た圧力を１００ ｋｇ／ｃｉから２００ ｋｇ／ｃｄに
変えた以外は、実施例１と同様にして抽出処理した。結
果を表に示す。Example 5 Extraction treatment was carried out in the same manner as in Example 1 except that the temperature was changed from 50°C to 40°C and the pressure was changed from 100 kg/ci to 200 kg/cd. The results are shown in the table.
（以下余白）
〔発明の効果］
本発明の方法によれば、塩化メチレン等の不純物を含有
するポリカーボネートを、低温かつ短時間で効果的に精
製することができ、その結果、極めて高純度のポリカー
ボネートを得ることができる。(Left below) [Effects of the Invention] According to the method of the present invention, polycarbonate containing impurities such as methylene chloride can be effectively purified at low temperatures and in a short time, and as a result, extremely high purity polycarbonate can be obtained. can be obtained.
したがって、本発明は光ディスク、磁気ディスク等のデ
ィスク基板等の用途に供される高品質のポリカーボネー
トを製造する際に、有効に利用される。Therefore, the present invention can be effectively utilized in manufacturing high-quality polycarbonate for use as disk substrates for optical disks, magnetic disks, and the like.
Claims (4)
臨界状態乃至超臨界状態の流体を用いて抽出処理するこ
とを特徴とするポリカーボネートの精製方法。(1) A method for purifying polycarbonate, which comprises extracting powdered polycarbonate containing impurities using a fluid in a subcritical or supercritical state.
１項記載の精製方法。(2) The purification method according to claim 1, wherein the impurity is methylene chloride.
である特許請求の範囲第１項記載の精製方法。(3) The purification method according to claim 1, wherein the fluid in a subcritical state or supercritical state is carbon dioxide.
ｋｇ／ｃｍ＾２および温度３０〜３００℃である特許請
求の範囲第１項記載の精製方法。(4) The subcritical state to supercritical state is at a pressure of 70 to 500
The purification method according to claim 1, wherein the purification method is performed at a temperature of 30 to 300°C.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP32677987A JPH0639524B2 (en) | 1987-12-25 | 1987-12-25 | Method for purifying polycarbonate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP32677987A JPH0639524B2 (en) | 1987-12-25 | 1987-12-25 | Method for purifying polycarbonate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01168730A true JPH01168730A (en) | 1989-07-04 |
| JPH0639524B2 JPH0639524B2 (en) | 1994-05-25 |
Family
ID=18191610
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP32677987A Expired - Lifetime JPH0639524B2 (en) | 1987-12-25 | 1987-12-25 | Method for purifying polycarbonate |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0639524B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0515948A2 (en) * | 1991-05-30 | 1992-12-02 | Bayer Ag | Process for the isolation of polycarbonates |
| US5229486A (en) * | 1990-12-20 | 1993-07-20 | Bayer Aktiengesellschaft | Process for isolating polymers from their solvents using liquids containing carbon dioxide |
-
1987
- 1987-12-25 JP JP32677987A patent/JPH0639524B2/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5229486A (en) * | 1990-12-20 | 1993-07-20 | Bayer Aktiengesellschaft | Process for isolating polymers from their solvents using liquids containing carbon dioxide |
| EP0515948A2 (en) * | 1991-05-30 | 1992-12-02 | Bayer Ag | Process for the isolation of polycarbonates |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0639524B2 (en) | 1994-05-25 |
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