JPH066607B2 - Method for producing vinyl chloride resin - Google Patents
Method for producing vinyl chloride resinInfo
- Publication number
- JPH066607B2 JPH066607B2 JP63206999A JP20699988A JPH066607B2 JP H066607 B2 JPH066607 B2 JP H066607B2 JP 63206999 A JP63206999 A JP 63206999A JP 20699988 A JP20699988 A JP 20699988A JP H066607 B2 JPH066607 B2 JP H066607B2
- Authority
- JP
- Japan
- Prior art keywords
- polymerization
- vinyl chloride
- reflux condenser
- suspension
- chloride resin
- 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 - Lifetime
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- Polymerisation Methods In General (AREA)
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は塩化ビニル系樹脂の製造方法に関し、更に詳し
くは、還流凝縮器を付設した重合反応器を用いて塩化ビ
ニル系樹脂を懸濁重合する方法の改善に関する。Description: TECHNICAL FIELD The present invention relates to a method for producing a vinyl chloride resin, more specifically, suspension polymerization of a vinyl chloride resin using a polymerization reactor equipped with a reflux condenser. On how to improve.
塩化ビニル系樹脂の製造に於いて、生産性向上及び省エ
ネルギーを図る目的で還流凝縮器がしばしば用いられ
る。しかし乍ら、還流凝縮器による冷却を伴なう懸濁重
合では、特に重合の初期に於いて重合系に著しい発泡現
象が現れ、重合開始剤を含む重合懸濁液の泡沫が重合反
応器の気相部内壁、重合反応器と還流凝縮器を結ぶ導管
及び還流凝縮器内壁に付着してスケールを形成し、これ
が還流凝縮器の熱効率を低下させるほか、フィッシュ・
アイなどの品質上を好ましくない結果を生じると共に、
スケールの除去作業に多大の労力を必要とするなど多く
の困難を伴なう。又、重合の中期以降に於いても、重合
懸濁液の粘度の上昇に伴ない撹拌効果が低下するため懸
濁液のホールドアップが増加し、極端な場合は上記導管
あるいは還流凝縮器内部へ懸濁液が溢流し、溢流した懸
濁液はそこで重合してスケールの塊となることがあり、
還流凝縮器を正常に稼働させることが困難となるばかり
でなく、フィッシュ・アイ等品質上も好ましくない結果
を生じる。In the production of vinyl chloride resin, a reflux condenser is often used for the purpose of improving productivity and saving energy. However, in suspension polymerization accompanied by cooling by a reflux condenser, a remarkable foaming phenomenon appears in the polymerization system particularly at the initial stage of the polymerization, and the foam of the polymerization suspension containing the polymerization initiator is generated in the polymerization reactor. In addition to adhering to the inner wall of the gas phase, the conduit connecting the polymerization reactor and the reflux condenser, and the inner wall of the reflux condenser to form scales, which reduces the thermal efficiency of the reflux condenser,
In addition to producing unfavorable results on the quality of eyes,
There are many difficulties such as requiring a great deal of work for the scale removal work. In addition, even after the middle stage of the polymerization, the stirring effect decreases as the viscosity of the polymerization suspension increases, and the hold-up of the suspension increases. The suspension overflows and the overflowed suspension may polymerize there into scale clumps,
Not only does it make it difficult to operate the reflux condenser normally, but also results in unfavorable quality such as fish eyes.
即ち、還流凝縮器を工業的に安定して使用する為には、
重合の全期間に亘って発泡に伴う懸濁液の還流凝縮器へ
の溢流を防止する必要がある。That is, in order to use the reflux condenser industrially stably,
It is necessary to prevent the suspension from overflowing the reflux condenser with foaming over the entire duration of the polymerization.
こうした状況に於いて、懸濁液の発泡防止については種
々の検討がなされてきており、重合中期以降の発泡につ
いては、還流凝縮器への冷却水の供給を調整することに
より発泡を抑制する方法（特開昭５７−２１２２１
２）、特定の重合触媒を組み合わせて使用する方法（特
公昭６２−１６０５）等の提案がなされている。Under these circumstances, various studies have been made to prevent the foaming of the suspension. For the foaming after the middle stage of polymerization, a method of suppressing the foaming by adjusting the supply of cooling water to the reflux condenser. (JP-A-57-21221
2), a method of using a specific polymerization catalyst in combination (Japanese Patent Publication No. 62-1605), and the like have been proposed.
しかし、重合初期の発泡は懸濁重合の安定化に使用する
分散剤が塩化ビニル系樹脂粒子に未吸着で水相中に存在
することに起因するものであって、この発泡防止は難し
く、品質的には粒度粗大化やフィッシュ・アイの悪化等
の悪影響が大きいので、重合初期の発泡防止は還流凝縮
器の工業的利用を図る上で重要な課題であった。However, the foaming at the initial stage of polymerization is due to the fact that the dispersant used for stabilizing the suspension polymerization is not adsorbed on the vinyl chloride resin particles and is present in the aqueous phase. However, since the adverse effects such as coarsening of particle size and deterioration of fish eyes are large, prevention of foaming at the initial stage of polymerization was an important issue for industrial use of the reflux condenser.
このような実情に鑑み、本発明者らは重合初期の発泡を
抑制すべく鋭意研究を重ねた結果、重合系内に予め非凝
縮ガスを導入しておくことにより、重合懸濁液の発泡を
完全に抑制し得ることを見出し、本発明を完成した。In view of such circumstances, the present inventors have conducted intensive studies to suppress foaming in the initial stage of polymerization, and as a result, by introducing a non-condensable gas into the polymerization system in advance, foaming of the polymerization suspension is suppressed. The present invention has been completed by finding that it can be completely suppressed.
即ち、本発明は重合反応器気相部又は重合反応器外に還
流凝縮器を付設した重合反応器を用いて、塩化ビニル単
量体単独又は塩化ビニル単量体とこれと共重合し得る他
の単量体との混合物を懸濁重合するに際し、予め重合系
内に非凝縮ガスを導入して重合を開始させ、然る後、前
記非凝縮ガスを重合系外にパージすることを特徴とする
塩化ビニル系樹脂の製造方法を内容とするものである。That is, according to the present invention, a vinyl chloride monomer alone or a vinyl chloride monomer and a copolymer with the vinyl chloride monomer can be copolymerized by using a polymerization reactor having a reflux condenser attached to the vapor phase part of the polymerization reactor or outside the polymerization reactor. In suspension-polymerizing the mixture with the monomer, the non-condensable gas is introduced into the polymerization system in advance to initiate the polymerization, and then the non-condensed gas is purged outside the polymerization system. The method for producing a vinyl chloride resin is described below.
重合系内に予め非凝縮ガスを導入することにより、重合
初期に於ける還流凝縮器での単量体の凝縮を防止し、そ
の結果重合懸濁液の発泡を抑制して還流凝縮器内部への
懸濁液の溢流を防止することができる。By introducing a non-condensable gas into the polymerization system beforehand, the condensation of the monomer in the reflux condenser at the initial stage of the polymerization is prevented, and as a result, the foaming of the polymerization suspension is suppressed to the inside of the reflux condenser. The overflow of the suspension can be prevented.
非凝縮ガスの重合系内への導入時期は、水、単量体の重
合反応器への仕込み前後のいずれでもよく特に限定され
ないが、遅くとも重合懸濁液の昇温を開始するまでには
導入しておくことが必要である。The time of introduction of the non-condensable gas into the polymerization system may be water or before or after charging the monomer to the polymerization reactor, and is not particularly limited, but it may be introduced by the time of starting the temperature rise of the polymerization suspension at the latest. It is necessary to keep it.
また、非凝縮ガスの導入量は、重合反応温度に於ける重
合反応器及び還流凝縮器の気相部空間容量に相当する量
が好ましいが、重合時に使用する分散剤や添加剤の種類
により重合懸濁液の発泡のし易さ程度が異なるので、必
ずしもこの導入量であることを要しない。The amount of non-condensed gas introduced is preferably an amount corresponding to the gas phase space capacity of the polymerization reactor and the reflux condenser at the polymerization reaction temperature, but depending on the type of dispersant or additive used during polymerization, the polymerization Since the degree of easiness of foaming of the suspension is different, it is not always necessary to use this amount.
導入した非凝縮ガスを重合開始後重合系外にパージし、
還流凝縮器のジャケット側に冷却水を通すことによって
還流凝縮器を稼動することができるが、その時期は重合
発熱量と重合反応器の除熱能力とのバランス及び重合懸
濁液の発泡のし易さを勘案して適宜選択すればよい。The introduced non-condensed gas was purged outside the polymerization system after the initiation of polymerization,
The reflux condenser can be operated by passing cooling water through the jacket side of the reflux condenser, but at that time, the balance between the heat generation amount of the polymerization and the heat removal capacity of the polymerization reactor and the foaming of the polymerization suspension are prevented. It may be selected as appropriate in consideration of ease.
尚、非凝縮ガスのパージは、重合懸濁液の発泡のし易さ
及び重合反応温度の制御安定性を考慮して還流凝縮器の
頂部から徐々に行うことが望ましい。The non-condensable gas is preferably purged gradually from the top of the reflux condenser in consideration of the ease of foaming of the polymerization suspension and the control stability of the polymerization reaction temperature.
また、非凝縮ガスの種類は特に限定されないが、コスト
及び製品となる塩化ビニル系樹脂の品質への影響等の観
点から窒素ガスが適当である。The type of non-condensable gas is not particularly limited, but nitrogen gas is suitable from the viewpoints of cost and influence on the quality of the vinyl chloride resin used as a product.
本発明に於いて塩化ビニル単量体と共重合し得る他の単
量体としては、例えばエチレン、プロピルなどのオレフ
ィン類、酢酸ビニル、ステアリン酸ビニルなどのビニル
エステル類、アクリル酸メチル、メタクリル酸メチルな
どのアクリル酸エステル類、マレイン酸またはフマル酸
などの酸のエステル類及び無水物、アクリロニトリルな
どのニトリル化合物、或いは塩化ビニリデンの如きビニ
リデン化合物等が上げられ、これらは単独又は２種類以
上組み合わせて使用される。Other monomers copolymerizable with the vinyl chloride monomer in the present invention include, for example, olefins such as ethylene and propyl, vinyl acetates such as vinyl acetate and vinyl stearate, methyl acrylate and methacrylic acid. Acrylic acid esters such as methyl, acid esters and anhydrides such as maleic acid or fumaric acid, nitrile compounds such as acrylonitrile, and vinylidene compounds such as vinylidene chloride are listed, and these may be used alone or in combination of two or more. used.
本発明に於いては使用される分散剤は公知の分散剤でよ
く、例えば部分鹸化ポリビニルアルコール、酢酸ビニル
−無水マレイン酸共重合体、スチレン−無水マレイン酸
共重合体、ポリビニルピロリドン、ゼラチン、デンプ
ン、メチルセルローズ、ヒドロキシプロピルセルローズ
などが挙げられ、これらは単独又は２種類以上組み合わ
せて使用される。また本発明に於いて使用される重合開
始剤としては、例えばアゾビスイソブチロニトリル、ア
ゾビス２，４−ジメチルバレロニトリル等のアゾ化合
物、ラウロイルパーオキサイド、ｔ−ブチルピバレー
ト、ジ−２−エチルヘキシルパーオキシジカーボネー
ト、イソプロピルパーオキシジカーボネート等の有機過
酸化物など公知の開始剤が挙げられ、これらは単独又は
２種類以上組み合わせて使用される。The dispersant used in the present invention may be a known dispersant, for example, partially saponified polyvinyl alcohol, vinyl acetate-maleic anhydride copolymer, styrene-maleic anhydride copolymer, polyvinylpyrrolidone, gelatin, starch. , Methyl cellulose, hydroxypropyl cellulose and the like, which may be used alone or in combination of two or more kinds. Examples of the polymerization initiator used in the present invention include azo compounds such as azobisisobutyronitrile and azobis2,4-dimethylvaleronitrile, lauroyl peroxide, t-butyl pivalate, and di-2-ethylhexylperoxide. Known initiators such as organic peroxides such as oxydicarbonate and isopropyl peroxydicarbonate may be used, and these may be used alone or in combination of two or more.
更に、本発明に於いて重合度調節剤としてのメルカプタ
ンジスルフィド、トリクロロエチレン等を、また添加物
としてのアルコール類、ヘキサン、ヘプタン等の飽和炭
化水素類、ベンゼン、トルエン等の芳香族類、ＤＯＰ、
エポキシ大豆油等の可塑剤類を併用しても何ら差し支え
ない。Further, in the present invention, mercaptan disulfide, trichloroethylene and the like as a polymerization degree controlling agent, alcohols as additives, saturated hydrocarbons such as hexane and heptane, aromatics such as benzene and toluene, DOP,
There is no problem even if plasticizers such as epoxy soybean oil are used together.
本発明に於ける重合反応温度範囲は通常４０〜７５℃で
あるが、特に限定されない。The polymerization reaction temperature range in the present invention is usually 40 to 75 ° C, but is not particularly limited.
本発明によれば、還流凝縮器を付設した重合反応器を用
いて塩化ビニル系樹脂を懸濁重合するに際し、重合反応
器を還流凝縮器と結ぶ導管及び還流凝縮器内に重合懸濁
液を溢流させることなく重合仕込量を増やすことが可能
となり、上記導管及び還流凝縮器内部でのスケール生成
を防止し、フィッシュ・アイ等の製品品質上の問題を生
じることもなく、還流凝縮器を継続して使用することが
可能となり、この工業的意義は極めて大きい。According to the present invention, during suspension polymerization of vinyl chloride resin using a polymerization reactor equipped with a reflux condenser, a polymerization suspension is provided in a conduit connecting the polymerization reactor to the reflux condenser and the reflux condenser. It is possible to increase the amount of polymerization charged without overflowing, prevent scale formation inside the above-mentioned conduit and reflux condenser, and without causing problems in product quality such as fish eyes and the like. It can be used continuously, and its industrial significance is extremely large.
以下、本発明の実施例及び比較例を示すが、これらは何
ら本発明を限定するものではない。Hereinafter, Examples and Comparative Examples of the present invention will be shown, but these do not limit the present invention in any way.
尚、得られた塩化ビニル樹脂については、下記の方法で
フイッシュ・アイを測定した。即ち、塩化ビニル樹脂１
００重量部、ＤＯＰ５０重量部、トリベース３重量部、
ステアリン酸０．５重量部、二酸化チタン０．４重量部
及びカーボンブラック０．２重量部を十分に混合し、１
４０℃の８インチロールで０．２ｍｍの厚みで８分間混
練してシートを作製し、シート１０cm×１０cm中のフィ
ッシュ・アイの個数を数えた。The obtained vinyl chloride resin was measured for fish eye by the following method. That is, vinyl chloride resin 1
00 parts by weight, DOP 50 parts by weight, Tribase 3 parts by weight,
Mix thoroughly 0.5 part by weight of stearic acid, 0.4 part by weight of titanium dioxide and 0.2 part by weight of carbon black,
A sheet was prepared by kneading with an 8-inch roll at 40 ° C. for a thickness of 0.2 mm for 8 minutes, and the number of fish eyes in the sheet 10 cm × 10 cm was counted.
実施例 空間容量が０．０５m3で伝熱面積が５m2である還流凝縮
器を付設した１．７m3重合反応器に、部分鹸化ポリビニ
ルアルコール０．０７重量部を溶解した水１２０重量部
を仕込み、重合開始剤ジ−２−エチルヘキシルパーオキ
シジカーボネート０．０２４重量部及びｔ−ブチルパー
オキシネオデカノエート０．０２４重量部を添加し、脱
気後０．３９Ｎm3の窒素ガスを導入し、続いて塩化ビニ
ル単量体１００重量部（６００kg）を装入した。重合反
応温度である５７℃まで昇温して重合を開始した後、還
流凝縮器の頂部から窒素ガスを重合系外に徐々にパージ
すると共に、還流凝縮器のジャケットに徐々に冷却水を
通し、重合開始後１時間目から重合反応器の内圧が定常
圧より１kg／cm2低下して未反応単量体の回収を開始す
るまでの間、還流凝縮器での除熱量が３０，０００kcal
/Hrとなるような条件で重合を行った。Example In a 1.7 m 3 polymerization reactor equipped with a reflux condenser having a space capacity of 0.05 m 3 and a heat transfer area of 5 m 2 , 120 parts by weight of water in which 0.07 parts by weight of partially saponified polyvinyl alcohol was dissolved was added. Charge, add 0.024 parts by weight of polymerization initiator di-2-ethylhexyl peroxydicarbonate and 0.024 parts by weight of t-butyl peroxyneodecanoate, and after degassing, introduce 0.39 Nm 3 of nitrogen gas. Then, subsequently, 100 parts by weight (600 kg) of a vinyl chloride monomer was charged. After the temperature was raised to 57 ° C. which is the polymerization reaction temperature to start the polymerization, nitrogen gas was gradually purged from the top of the reflux condenser to the outside of the polymerization system, and cooling water was gradually passed through the jacket of the reflux condenser. From the first hour after the start of polymerization until the internal pressure of the polymerization reactor drops 1 kg / cm 2 below the steady pressure and the recovery of unreacted monomer is started, the heat removal amount in the reflux condenser is 30,000 kcal.
Polymerization was carried out under the condition of / Hr.
この方法により、還流凝縮器内部を清掃することなく合
計１０バッチの重合を行った後、還流凝縮器を解体して
内部を点検したが、還流凝縮器内部及び重合反応器と還
流凝縮器を結ぶ導管には重合体粒子やスケールの付着は
認められなかった。According to this method, after performing a total of 10 batches of polymerization without cleaning the inside of the reflux condenser, the reflux condenser was disassembled and the inside was inspected. The inside of the reflux condenser and the polymerization reactor and the reflux condenser were connected. No adhesion of polymer particles or scale was found in the conduit.
また１０バッチ目の製品のフイッシュ・アイは３個の良
好であった。The 10th batch product had 3 good fish eyes.
比較例 実施例に於いて、窒素ガスを導入しない他は、同様にし
て重合を行った。Comparative Example Polymerization was carried out in the same manner as in Example except that nitrogen gas was not introduced.
この方法により還流凝縮器を清掃することなく２バッチ
目の重合を行なった後、還流凝縮器内部及び重合反応器
と還流凝縮器を結ぶ導管を点検したところ、溢流した重
合体粒子が存在し、フィルム状スケールが生成してい
た。After the second batch of polymerization was carried out by this method without cleaning the reflux condenser, the inside of the reflux condenser and the conduit connecting the polymerization reactor and the reflux condenser were inspected, and overflowed polymer particles were found. , A film-like scale had formed.
２バッチ目の製品のフィッシュ・アイは７５個と非常に
多いものであった。The number of fish eyes in the product of the second batch was 75, which was very large.
Claims (2)
凝縮器を付設した重合反応器を用いて、塩化ビニル単量
体単独又は塩化ビニル単量体とこれと共重合し得る他の
単量体との混合物を懸濁重合するに際し、予め重合系内
に非凝縮ガスを導入して重合を開始させ、然る後、前記
非凝縮ガスを重合系外にパージすることを特徴とする塩
化ビニル系樹脂の製造方法。1. A vinyl chloride monomer alone or a vinyl chloride monomer and a vinyl chloride monomer can be copolymerized with a vinyl chloride monomer by using a polymerization reactor having a reflux condenser attached to the vapor phase part of the polymerization reactor or outside the polymerization reactor. In suspension-polymerizing the mixture with the monomer, the non-condensable gas is introduced into the polymerization system in advance to initiate the polymerization, and then the non-condensed gas is purged outside the polymerization system. A method for producing a vinyl chloride resin.
造方法。2. The method according to claim 1, wherein the non-condensing gas is nitrogen.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63206999A JPH066607B2 (en) | 1988-08-19 | 1988-08-19 | Method for producing vinyl chloride resin |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63206999A JPH066607B2 (en) | 1988-08-19 | 1988-08-19 | Method for producing vinyl chloride resin |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0255707A JPH0255707A (en) | 1990-02-26 |
| JPH066607B2 true JPH066607B2 (en) | 1994-01-26 |
Family
ID=16532516
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63206999A Expired - Lifetime JPH066607B2 (en) | 1988-08-19 | 1988-08-19 | Method for producing vinyl chloride resin |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH066607B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011070048A (en) * | 2009-09-28 | 2011-04-07 | Canon Inc | Method for producing polymerized toner |
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|---|---|---|---|---|
| JPS4888186A (en) * | 1972-02-02 | 1973-11-19 | ||
| JPS4982789A (en) * | 1972-12-14 | 1974-08-09 | ||
| JPS5338311A (en) * | 1976-09-21 | 1978-04-08 | Oki Electric Ind Co Ltd | Reading system |
| JPS53114891A (en) * | 1977-02-24 | 1978-10-06 | Mitsui Toatsu Chem Inc | Suspension polymerization of vinyl chloride |
| JPS6136301A (en) * | 1984-07-27 | 1986-02-21 | Kanegafuchi Chem Ind Co Ltd | Method for controlling temperature in polymerization reactor |
-
1988
- 1988-08-19 JP JP63206999A patent/JPH066607B2/en not_active Expired - Lifetime
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS4888186A (en) * | 1972-02-02 | 1973-11-19 | ||
| JPS4982789A (en) * | 1972-12-14 | 1974-08-09 | ||
| JPS5338311A (en) * | 1976-09-21 | 1978-04-08 | Oki Electric Ind Co Ltd | Reading system |
| JPS53114891A (en) * | 1977-02-24 | 1978-10-06 | Mitsui Toatsu Chem Inc | Suspension polymerization of vinyl chloride |
| JPS6136301A (en) * | 1984-07-27 | 1986-02-21 | Kanegafuchi Chem Ind Co Ltd | Method for controlling temperature in polymerization reactor |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011070048A (en) * | 2009-09-28 | 2011-04-07 | Canon Inc | Method for producing polymerized toner |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0255707A (en) | 1990-02-26 |
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