JP2000302805A - Manufacture of vinyl chloride resin - Google Patents
Manufacture of vinyl chloride resinInfo
- Publication number
- JP2000302805A JP2000302805A JP11112878A JP11287899A JP2000302805A JP 2000302805 A JP2000302805 A JP 2000302805A JP 11112878 A JP11112878 A JP 11112878A JP 11287899 A JP11287899 A JP 11287899A JP 2000302805 A JP2000302805 A JP 2000302805A
- Authority
- JP
- Japan
- Prior art keywords
- vinyl chloride
- weight
- monomer
- polymerization
- parts
- 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.)
- Pending
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- Polymerisation Methods In General (AREA)
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
Abstract
Description
【0001】[0001]
【発明の属する技術分野】本発明は塩化ビニル系樹脂の
製造法およびその樹脂組成物に関するものであり、詳細
には重合時のスケール防止効果がありかつ加工性および
熱的安定性に優れる塩化ビニル系樹脂の製造法に関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a vinyl chloride resin and a resin composition thereof. More specifically, the present invention relates to a vinyl chloride resin having an effect of preventing scale during polymerization and having excellent processability and thermal stability. The present invention relates to a method for producing a resin.
【0002】[0002]
【従来の技術】塩化ビニル系樹脂は安価でかつ品質バラ
ンスに優れているため、硬質分野、軟質分野など種々の
広範な分野で利用されている熱可塑性樹脂であり、その
用途として、たとえば硬質分野ではパイプや継手、窓
枠、工業用透明板、フィルムなどが、軟質分野では電線
被覆、ラップフィルム、シートなどがそれぞれあげられ
る。2. Description of the Related Art Vinyl chloride resins are inexpensive and have an excellent balance of quality. Therefore, they are thermoplastic resins used in various fields such as hard fields and soft fields. Examples include pipes and joints, window frames, industrial transparent plates, films, etc., and in the field of soft materials, electric wire coatings, wrap films, sheets, and the like.
【0003】材料としての塩化ビニル系樹脂は安価なこ
とが必須である汎用樹脂であるが、性能面でも種々の特
性が要求され、たとえば前述の軟質用途分野における製
品では高い体積固有抵抗値、良好な可塑剤吸収性、フィ
ッシュアイの抑制などがあげられる。[0003] A vinyl chloride resin as a material is a general-purpose resin which is indispensable to be inexpensive. However, various characteristics are required also in terms of performance. Plasticizer absorption and suppression of fish eyes.
【0004】一方硬質用途分野においては、種々成形体
に加工する際の加工性・熱的安定性、成形後の引張強度
や衝撃強度などの基本物性などが良好であることが求め
られる。これらの要求特性を改良するために様々な工夫
がなされてきており、これまでに開示された技術にも数
多く見ることができる。たとえば特開平9−27896
4号公報には、耐衝撃性および成形加工性向上のために
塩化ビニル系樹脂にメタクリル酸メチル・ブタジエン・ス
チレン共重合体または塩素化ポリエチレンを添加する方
法、特開平10−1584号公報には熱安定性や加工性
などの向上のために塩化ビニル系樹脂にカルシウム化合
物、亜鉛化合物、エポキシ化植物油、β−ジケトン化合
物およびエステル系化合物を添加する方法、特開平10
−17744号公報には成形加工性改善のために塩化ビ
ニル系樹脂に塩素化ポリオレフィンおよび/またはビニ
ルエステル―エチレン共重合体を配合する方法などが開
示されている。On the other hand, in the field of hard applications, good workability and thermal stability when processing into various molded articles, and good basic physical properties such as tensile strength and impact strength after molding are required. Various attempts have been made to improve these required characteristics, and many can be seen in the techniques disclosed so far. For example, JP-A-9-27896
JP-A-10-1584 discloses a method of adding a methyl methacrylate-butadiene-styrene copolymer or chlorinated polyethylene to a vinyl chloride resin in order to improve impact resistance and molding processability. A method of adding a calcium compound, a zinc compound, an epoxidized vegetable oil, a β-diketone compound and an ester compound to a vinyl chloride resin in order to improve thermal stability and processability;
Japanese Patent Application No. 17744 discloses a method of blending a chlorinated polyolefin and / or a vinyl ester-ethylene copolymer with a vinyl chloride resin in order to improve moldability.
【0005】しかしながら、これらの方法ではいずれも
各種強化剤や添加剤を配合しており、概して多種多量の
強化剤・添加剤が必要となる。さらにポリ塩化ビニル系
樹脂を重合する際に、重合容器内の内壁やモノマー還流
装置内壁や系内の配管内壁にスケールが付着し品質の低
下および重合時の除熱不良を引き起こさないために様々
なスケール防止剤を塗布して重合される。However, all of these methods contain various reinforcing agents and additives, and generally require a large amount of various reinforcing agents and additives. Furthermore, when polymerizing polyvinyl chloride resin, various scales are used to prevent scale from adhering to the inner wall of the polymerization vessel, the inner wall of the monomer reflux unit, and the inner wall of the piping in the system, causing deterioration in quality and poor heat removal during polymerization. It is polymerized by applying a scale inhibitor.
【0006】[0006]
【発明が解決しようとする課題】本発明は前記従来技術
に鑑みてなされたものであり、重合時のスケール付着が
少なく、加工性および熱的安定性に優れかつ物性低下の
ない塩化ビニル系樹脂の製造法を提供することを目的と
する。DISCLOSURE OF THE INVENTION The present invention has been made in view of the above-mentioned prior art, and is a vinyl chloride resin having little scale adhesion during polymerization, excellent in processability and thermal stability, and having no deterioration in physical properties. An object of the present invention is to provide a method for producing the same.
【0007】[0007]
【課題を解決するための手段】本発明者らは、重合時の
スケール付着が少なく、品質上の要求特性すなわち加工
性および熱的安定性に優れかつ物性低下のない塩化ビニ
ル系樹脂の製造法について鋭意検討した結果、塩化ビニ
ル単量体、または塩化ビニル単量体と共重合可能な単量
体と塩化ビニル単量体との混合物を水性媒体中で懸濁重
合させる際に、特定の分散剤を組み合わせて用いること
により何ら問題点を生じることなく要求特性に優れた塩
化ビニル系樹脂組成物を得ることができることを見出
し、本発明に至った。DISCLOSURE OF THE INVENTION The present inventors have developed a method for producing a vinyl chloride resin which has little scale adhesion during polymerization and has excellent properties required for quality, that is, excellent processability and thermal stability and has no deterioration in physical properties. As a result of intensive studies on vinyl chloride monomer or a mixture of vinyl chloride monomer and a monomer copolymerizable with vinyl chloride monomer, a specific dispersion The present inventors have found that a vinyl chloride resin composition excellent in required characteristics can be obtained without any problem by using a combination of the agents, and the present invention has been accomplished.
【0008】すなわち本発明は、塩化ビニル単量体、ま
たは塩化ビニル単量体と共重合可能な単量体と塩化ビニ
ル単量体との混合物を水性媒体中で懸濁重合させる際
に、塩化ビニル単量体、または塩化ビニル単量体と共重
合可能な単量体と塩化ビニル単量体との混合物(以下、
「塩化ビニル系単量体」という)に対し、懸濁分散剤と
して、(a)鹸化度が70〜85%、平均重合度が15
00〜2500である部分鹸化ポリ酢酸ビニル、(b)
鹸化度が33〜70%、平均重合度が200〜1000
である部分鹸化ポリ酢酸ビニル、および(c)キトサン
の有機酸水溶液を用いることを特徴とする塩化ビニル系
樹脂の製造法(請求項1)、塩化ビニル系単量体100
重量部に対し、懸濁分散剤として、前記(a)を0.0
2〜0.08重量部、前記(b)を0.01〜0.05
重量部、および前記(c)を0.005〜0.2重量部
用いることを特徴とする請求項1記載の塩化ビニル系樹
脂の製造法(請求項2)、および塩化ビニル系単量体1
00重量部に対し、懸濁分散剤として、前記(a)、
(b)および(c)を、(a)/(b)=1/1〜5/
1の比率で(a)+(b)の合計部数が0.02〜0.
08重量部、(a+b)/(c)=1/10〜10/1
の比率で(c)を0.005〜0.2重量部用いること
を特徴とする請求項1記載の塩化ビニル系樹脂の製造法
(請求項3)をその内容とする。That is, the present invention relates to a method for preparing a vinyl chloride monomer or a mixture of a monomer copolymerizable with the vinyl chloride monomer and a vinyl chloride monomer in suspension polymerization in an aqueous medium. Vinyl monomer, or a mixture of a monomer copolymerizable with a vinyl chloride monomer and a vinyl chloride monomer (hereinafter, referred to as
(Referred to as “vinyl chloride monomer”), (a) a saponification degree of 70 to 85% and an average polymerization degree of 15
(B) partially saponified polyvinyl acetate which is from 00 to 2500;
Saponification degree is 33-70%, average polymerization degree is 200-1000
Using a partially saponified polyvinyl acetate and an organic acid aqueous solution of (c) chitosan (claim 1).
The above (a) was used as a suspending and dispersing agent in an amount of 0.0
2 to 0.08 parts by weight, 0.01 to 0.05 of the above (b)
2. The method for producing a vinyl chloride resin according to claim 1, wherein 0.005 to 0.2 parts by weight of (c) is used, and the vinyl chloride monomer 1 is used.
With respect to 00 parts by weight, the above-mentioned (a)
(B) and (c) are calculated as follows: (a) / (b) = 1/1 to 5 /
And the total number of copies of (a) + (b) is 0.02-0.
08 parts by weight, (a + b) / (c) = 1/10 to 10/1
(C) is used in an amount of 0.005 to 0.2 parts by weight in the ratio of (3).
【0009】[0009]
【発明の実施の形態】本発明は、塩化ビニル系単量体を
水性媒体中で懸濁重合させる際に、塩化ビニル系単量体
に対し、懸濁分散剤として、(a)鹸化度が70〜85
%、平均重合度が1500〜2500である部分鹸化ポ
リ酢酸ビニル、(b)鹸化度が33〜70%、平均重合
度が200〜1000である部分鹸化ポリ酢酸ビニル、
および(c)キトサンの有機酸水溶液を用いることを特
徴とする塩化ビニル系樹脂の製造法である。BEST MODE FOR CARRYING OUT THE INVENTION According to the present invention, when a vinyl chloride monomer is subjected to suspension polymerization in an aqueous medium, (a) a saponification degree is used as a suspending / dispersing agent with respect to the vinyl chloride monomer. 70-85
%, Partially saponified polyvinyl acetate having an average degree of polymerization of 1500 to 2500, (b) partially saponified polyvinyl acetate having a saponification degree of 33 to 70% and an average degree of polymerization of 200 to 1000,
And (c) a method for producing a vinyl chloride resin, which comprises using an aqueous solution of chitosan in an organic acid.
【0010】本発明に用いられる塩化ビニル系樹脂の製
造には、これら3種の分散剤を併用することが必須であ
る。ただし、上記3種類の分散剤以外にもメチルセルロ
ースやポリエチレンオキサイドなどの懸濁安定剤として
働く高分子水溶液を添加しても本発明に関する特性を失
うものではない。For the production of the vinyl chloride resin used in the present invention, it is essential to use these three dispersants in combination. However, even if an aqueous polymer solution serving as a suspension stabilizer such as methylcellulose or polyethylene oxide is added in addition to the above three dispersants, the characteristics of the present invention are not lost.
【0011】(a)は塩化ビニル系樹脂を製造する際、
最も一般的に用いられる部分鹸化ポリ酢酸ビニル(以
下、「PVA」という)といってよく、重合安定性が非
常に高い。(a)の鹸化度は70〜85%である。鹸化
度が70%未満では界面活性が強くなりすぎるとともに
水に溶け難くなるため扱いが困難とり、また鹸化度が8
5%をこえると界面活性不足により重合反応が安定に進
行しにくい。この(a)の平均重合度は1500〜25
00、好ましくは1800〜2200である。平均重合
度が1500未満では重合反応を安定に進行させるため
に使用量を増やすことが必要で、結果として樹脂表面分
散剤膜の厚みが厚くなりすぎる。一方、平均重合度が2
500をこえると、用いる量が少なくても樹脂表面分散
剤膜の厚みが厚くなりすぎる。このように、いずれの場
合も好ましくない。(A) is a method for producing a vinyl chloride resin,
It may be referred to as the most commonly used partially saponified polyvinyl acetate (hereinafter referred to as "PVA"), and has extremely high polymerization stability. The saponification degree of (a) is 70 to 85%. If the saponification degree is less than 70%, the surface activity becomes too strong and it becomes difficult to dissolve in water, so that it is difficult to handle.
If it exceeds 5%, the polymerization reaction is difficult to proceed stably due to insufficient surface activity. The average polymerization degree of this (a) is 1500 to 25
00, preferably 1800 to 2200. If the average degree of polymerization is less than 1500, it is necessary to increase the amount used in order to allow the polymerization reaction to proceed stably, and as a result, the thickness of the resin surface dispersant film becomes too thick. On the other hand, when the average degree of polymerization is 2
If it exceeds 500, the thickness of the resin surface dispersant film becomes too thick even if the amount used is small. Thus, neither case is preferred.
【0012】(a)の添加量は塩化ビニル系単量体10
0重量部に対し、0.02〜0.08重量部用いること
が好ましい。この量が0.02重量部未満では重合を安
定に進行させることが出来ず、また、0.08重量部を
こえると生成する樹脂表面の分散剤膜が厚くなり加工性
を損なう。The amount of (a) added is 10
It is preferable to use 0.02 to 0.08 parts by weight with respect to 0 parts by weight. If the amount is less than 0.02 parts by weight, the polymerization cannot proceed stably, and if it exceeds 0.08 parts by weight, the resulting dispersant film on the resin surface becomes thick and impairs the processability.
【0013】(b)は加工性改良のために樹脂内部を高
多孔質とするのに適したPVAと言えるが、単独では重
合反応を安定に進行させることが非常に困難であり、
(a)のようなPVAなどを併用することが必要であ
る。(b)の鹸化度は33〜70%である。鹸化度が3
3%未満では水に対する溶解性、あるいは膨潤性があま
りにも低下しすぎて樹脂内部の多孔性を高める効果が発
現し難くなる。また鹸化度が70%をこえると単量体へ
の溶解性が実質的になくなり、樹脂内部を多孔性にする
効果が期待できない。この(b)の平均重合度は200
〜1000、好ましくは300〜700である。平均重
合度が200未満では単量体への溶解度があまりにも大
きすぎて初期に生成する単量体油滴が不安定となり、重
合反応が正常に進行できない。平均重合度が1000を
こえると逆に単量体への溶解度が低すぎて生成する樹脂
内部の多孔度を高くできない。(B) can be said to be a PVA suitable for making the inside of the resin highly porous in order to improve the processability, but it is very difficult to progress the polymerization reaction stably by itself,
It is necessary to use PVA as in (a) in combination. The saponification degree of (b) is 33 to 70%. Saponification degree 3
If it is less than 3%, the solubility in water or the swelling property is so reduced that the effect of increasing the porosity inside the resin is hardly exhibited. If the degree of saponification exceeds 70%, the solubility in the monomer is substantially lost, and the effect of making the inside of the resin porous cannot be expected. The average degree of polymerization of this (b) is 200
10001000, preferably 300-700. If the average degree of polymerization is less than 200, the solubility in the monomer is too large, so that the initially formed monomer oil droplets become unstable, and the polymerization reaction cannot proceed normally. If the average degree of polymerization exceeds 1,000, on the contrary, the solubility in the monomer is too low, and the porosity inside the formed resin cannot be increased.
【0014】(b)の添加量は、塩化ビニル系単量体1
00重量部に対して、0.01〜0.05重量部用いる
ことが好ましい。この量が0.01重量部未満では、樹
脂内部の多孔性効果が発現しなく、また0.05重量部
をこえると、単量体の油滴の分散性が高くなりすぎて重
合を安定に進行させることが困難となる。The amount of (b) to be added is as follows.
It is preferable to use 0.01 to 0.05 parts by weight based on 00 parts by weight. If this amount is less than 0.01 part by weight, the porous effect inside the resin will not be exhibited, and if it exceeds 0.05 part by weight, the dispersibility of the oil droplets of the monomer will be too high to stabilize the polymerization. It is difficult to progress.
【0015】(c)のキトサンの有機酸水溶液は、PV
Aなどで覆われた単量体油滴どうしが衝突によって融着
するのを抑制する効果(油滴保護力)と重合容器内壁に
単量体油滴が衝突し破泡し付着する事によって発生する
スケールが少なくなる効果を示す。(c)の添加量は、
塩化ビニル系単量体100重量部に対して、0.005
〜0.2重量部用いることが好ましい。0.005重量
部未満では重合反応が安定に進行せず異常重合を起こ
し、0.2重量部をこえると得られる樹脂の粒径が非常
に小さくなる。なぜなら(c)の分散剤は他の分散剤と
は異なり界面活性能力をほとんど有しないためである。
また分子量が大きく、したがって粘度が非常に高く著し
い増粘効果を示すことが特徴であり、水/単量体油滴界
面の水側に局在し、油滴保護力が非常に高い。また著し
い高粘度の故に極く少量でこの融着抑制効果を示す。こ
の作用によって他の分散剤の使用量を大幅に減らすこと
が可能となり、とくにここで用いる(a)および(b)
のような分散剤量を減らすことは表面の分散剤膜を薄く
することにつながり有益である。The organic acid aqueous solution of chitosan (c) is PV
The effect of suppressing the adhesion of monomer oil droplets covered with A etc. due to collision (oil droplet protection) and the occurrence of monomer oil droplets colliding with the inner wall of the polymerization vessel, breaking and adhering The effect of reducing the scale to be performed is shown. The amount of (c) added is
0.005 to 100 parts by weight of the vinyl chloride monomer
It is preferable to use 0.2 to 0.2 parts by weight. If the amount is less than 0.005 parts by weight, the polymerization reaction does not proceed stably and abnormal polymerization occurs. If the amount exceeds 0.2 parts by weight, the particle size of the obtained resin becomes extremely small. This is because the dispersant (c) has almost no surface active ability unlike other dispersants.
It is also characterized by a high molecular weight and therefore a very high viscosity, exhibiting a remarkable thickening effect. It is localized on the water side of the water / monomer oil droplet interface and has a very high oil droplet protection power. In addition, due to the remarkably high viscosity, the effect of suppressing fusion is exhibited in a very small amount. This effect makes it possible to greatly reduce the amount of other dispersants used, in particular the (a) and (b)
Reducing the amount of the dispersant as described above is beneficial because it leads to a thinner dispersant film on the surface.
【0016】キトサンの有機酸水溶液に用いられる有機
酸は酢酸が最も好ましい。本キトサン水溶液の調製に使
用される有機酸水溶液は0.1〜1.0%の濃度のもの
が好適に使用され、キトサンの濃度は当該有機酸水溶液
への溶解度に依存し0.03〜3.0重量%となる。仕
込み時のハンドリング性の点からは、0.03〜1.0
重量%キトサンの酢酸水溶液がとくに好ましい。The most preferred organic acid used in the aqueous solution of chitosan in organic acid is acetic acid. The aqueous solution of the organic acid used for the preparation of the present chitosan aqueous solution preferably has a concentration of 0.1 to 1.0%, and the concentration of chitosan depends on the solubility in the organic acid aqueous solution. 0.0% by weight. From the point of handling at the time of preparation, 0.03 to 1.0
An aqueous solution of acetic acid in weight% chitosan is particularly preferred.
【0017】前記(a)および(b)2種の懸濁分散剤
を、塩化ビニル系単量体100重量部に対し、(a)/
(b)=1/1〜5/1の比率で(a)+(b)の合計
部数が0.02〜0.08重量部、好ましくは0.04
〜0.07重量部で用いる。(a)/(b)の比率が1
/1未満では、重合を安定に進行させることが出来ず、
5/1をこえると、生成する樹脂の表面の分散剤膜が厚
くなりすぎたり、粒子径が小さくなりすぎて加工性に悪
影響を与える。The above two types of suspending and dispersing agents (a) and (b) are used in an amount of (a) / 100 parts by weight of the vinyl chloride monomer.
(B) = A total of (a) + (b) in a ratio of 1/1 to 5/1 is 0.02 to 0.08 parts by weight, preferably 0.04 parts by weight.
Used at で 0.07 parts by weight. (A) / (b) ratio is 1
If it is less than / 1, polymerization cannot proceed stably,
If the ratio exceeds 5/1, the thickness of the dispersant film on the surface of the resin to be formed becomes too thick or the particle diameter becomes too small, which adversely affects the processability.
【0018】(a)+(b)の合計部数が0.02重量
部未満では重合反応を安定に進行させることができず、
0.08重量部をこえると生成する樹脂表面の分散剤膜
が厚くなりすぎて加工性に悪影響を及ぼす。また、塩化
ビニル系単量体100重量部に対して、前記2種の懸濁
分散剤と(a+b)/(c)=1/10〜10/1の比
率で(c)を0.005〜0.2重量部用いる。(a+
b)/(c)の比率が1/10未満では、重合初期の単
量体の油滴を形成させるための分散力が不足し重合を安
定に進行させることが出来ず、10/1をこえると、ス
ケール付着効果が損なわれる。(c)が0.005重量
部未満では重合反応が安定に進行せず異常重合を起こ
し、0.2重量部をこえると得られる樹脂の粒径が非常
に小さくなる。If the total number of (a) + (b) is less than 0.02 parts by weight, the polymerization reaction cannot proceed stably.
If the amount exceeds 0.08 parts by weight, the resulting dispersant film on the resin surface becomes too thick, which adversely affects the processability. Further, with respect to 100 parts by weight of the vinyl chloride monomer, (c) was added to the above two kinds of suspending dispersants at a ratio of (a + b) / (c) = 1/10 to 10/1, and 0.005 to 0.005. Use 0.2 parts by weight. (A +
When the ratio of b) / (c) is less than 1/10, the dispersing power for forming oil droplets of the monomer in the initial stage of polymerization is insufficient, so that the polymerization cannot proceed stably and exceeds 10/1. Then, the scale adhesion effect is impaired. If (c) is less than 0.005 parts by weight, the polymerization reaction does not proceed stably and abnormal polymerization occurs. If it exceeds 0.2 parts by weight, the particle size of the obtained resin becomes extremely small.
【0019】本発明に用いられる塩化ビニル系樹脂を製
造する際に使用する単量体は塩化ビニルを主成分とする
単量体であり、具体的には、塩化ビニル単量体単独、ま
たは塩化ビニル単量体と共重合可能な単量体と塩化ビニ
ル単量体からなる塩化ビニル単量体を70重量%以上含
有する混合物である。The monomer used in producing the vinyl chloride resin used in the present invention is a monomer containing vinyl chloride as a main component, and specifically, a vinyl chloride monomer alone or a vinyl chloride monomer. It is a mixture containing 70% by weight or more of a vinyl chloride monomer composed of a monomer copolymerizable with a vinyl monomer and a vinyl chloride monomer.
【0020】塩化ビニル単量体と共重合可能な単量体と
しては、たとえば酢酸ビニル、プロピオン酸ビニルなど
のビニルエステル類、エチレン、プロピレン、イソブチ
ルビニルエーテルなどのα−オレフィン類、1−クロロ
プロピレン、2−クロロブチレンなどのクロル化オレフ
ィン類、(メタ)アクリル酸メチルなどの(メタ)アク
リル酸エステル類、無水マレイン酸、アクリロニトリ
ル、スチレン、塩化ビニリデンなどがあげられ、これら
は単独で用いることも、2種以上組み合わせて用いるこ
とも可能である。Examples of the monomer copolymerizable with the vinyl chloride monomer include vinyl esters such as vinyl acetate and vinyl propionate, α-olefins such as ethylene, propylene and isobutyl vinyl ether, 1-chloropropylene, Chlorinated olefins such as 2-chlorobutylene, (meth) acrylates such as methyl (meth) acrylate, maleic anhydride, acrylonitrile, styrene, vinylidene chloride and the like can be mentioned, and these can be used alone. Two or more kinds can be used in combination.
【0021】塩化ビニル系樹脂を製造する際、本発明に
用いられる原料の仕込み方法は公知の技術を任意に用い
ることができる。たとえば最も一般的な方法として、先
に水を仕込んだ後単量体を仕込む方法、重合温度まで昇
温する時間を短縮する目的で先に単量体を仕込んだ後温
水を仕込む方法、さらに仕込みおよび昇温時間を短縮す
る目的で単量体と温水を同時に仕込む方法などを用いる
ことができる。In producing the vinyl chloride resin, a known technique can be used for the method of charging the raw materials used in the present invention. For example, the most common methods are to first charge water and then charge the monomer, to charge the monomer first to reduce the time required to raise the temperature to the polymerization temperature, and then to charge hot water. In addition, a method of simultaneously charging the monomer and the hot water for the purpose of shortening the heating time can be used.
【0022】また重合反応熱の除去は、従来の方式、た
とえば外部あるいは内部ジャケットによる除熱、還流凝
縮器による方法などを利用すれば良い。The heat of the polymerization reaction may be removed by a conventional method such as heat removal by an external or internal jacket, a method by a reflux condenser, and the like.
【0023】さらに従来塩化ビニル系単量体の重合また
は共重合に使用される重合開始剤、重合度調節剤、連鎖
移動剤、pH調節剤、ゲル化性改良剤、帯電防止剤、乳
化剤、安定剤、スケール防止剤などやこれらの仕込方法
も公知の技術をなんら支障なく任意に用いることがで
き、その使用量も従来公知の方法に従うことができる。Further, polymerization initiators, polymerization degree regulators, chain transfer agents, pH regulators, gelling improvers, antistatic agents, emulsifiers, and stabilizers conventionally used in the polymerization or copolymerization of vinyl chloride monomers. Any known technique can be used without any hindrance for the agent, scale inhibitor, etc., and their preparation methods can also be used, and the amounts used can be in accordance with conventionally known methods.
【0024】[0024]
【実施例】本発明をさらに具体的に説明するために、以
下に実施例および比較例を示すが、これら実施例は本発
明をなんら限定するものではない。なお、本実施例の水
は全てイオン交換水を用いた。得られた塩化ビニル系樹
脂の特性値の測定および組成物の加工性・熱的安定性・
物性の評価は次の方法により実施した。EXAMPLES The present invention will be described more specifically with reference to the following Examples and Comparative Examples, which are not intended to limit the present invention. In addition, all the water of this example used ion-exchange water. Measurement of characteristic values of the obtained vinyl chloride resin and processability, thermal stability,
Evaluation of physical properties was performed by the following methods.
【0025】(1)平均粒子径、粒度分布 JIS K−6721に準拠し、42、60、80、1
00、120、145、200メッシュの篩を使用し、
篩振とう器にて篩分けを行い、50%通過径をもって平
均粒子径(μm)とした。また粒度分布は、各メッシュ
に残留した塩化ビニル系樹脂の重量を測定し、重量百分
率にて表示した。このうち42メッシュ上に残留した樹
脂の量は百分率に含めず粗粒分とし、200メッシュを
通過した量はPASS分とした。(1) Average particle size and particle size distribution According to JIS K-6721, 42, 60, 80, 1
Using a sieve of 00, 120, 145, 200 mesh,
The particles were sieved with a sieve shaker, and the average particle diameter (μm) was determined using a 50% passage diameter. The particle size distribution was measured by measuring the weight of the vinyl chloride resin remaining on each mesh and expressed as a weight percentage. Of these, the amount of resin remaining on the 42 mesh was not included in the percentage and was regarded as coarse particles, and the amount of resin that passed through the 200 mesh was regarded as PASS.
【0026】(2)多孔度 水銀圧入式ポロシメーター(5−7118型、AMINCO社
製)を用いて、絶対圧31〜1011psi(ポア口径
0.175〜5.65μm)の間で塩化ビニル系樹脂に
圧入される水銀の容量を測定し、塩化ビニル系樹脂10
0gあたりの圧入水銀量(cc)を算出した。(2) Porosity Using a mercury intrusion porosimeter (Model 5-7118, manufactured by AMINCO), a vinyl chloride resin is applied at an absolute pressure of 31 to 1011 psi (pore diameter of 0.175 to 5.65 μm). Measure the volume of mercury injected, and measure the vinyl chloride resin 10
The amount of injected mercury (cc) per 0 g was calculated.
【0027】(3)加工性 塩化ビニル系樹脂100重量部に有機錫系安定剤0.5
重量部、脂肪酸エステル系滑剤0.1重量部、ポリエチ
レン系滑剤0.2重量部を添加し十分撹拌混合した後、
表面温度を170℃、180℃または190℃に調節し
た8インチロールに投入した。それぞれの温度で5分間
混練して厚み約0.5mmのロールシートを取り出し、
シートの仕上がり状態を目視で確認して、加工性を以下
の評価基準にしたがって三段階で評価した。 ○…十分混練され均一なシートが得られる。 △…やや混練不十分でシートにも不均一な部分が見られ
る。 ×…まったく混練不十分で、シートも至る所に穴が開い
ている。(3) Processability 100 parts by weight of vinyl chloride resin and 0.5 parts of an organic tin stabilizer
Parts by weight, 0.1 part by weight of a fatty acid ester-based lubricant, and 0.2 parts by weight of a polyethylene-based lubricant, and after sufficiently stirring and mixing,
It was put into an 8-inch roll whose surface temperature was adjusted to 170 ° C, 180 ° C or 190 ° C. Kneading at each temperature for 5 minutes, taking out a roll sheet of about 0.5 mm thickness,
The finished state of the sheet was visually checked, and the workability was evaluated in three steps according to the following evaluation criteria. …: Sufficiently kneaded to obtain a uniform sheet. Δ: Some unevenness was observed in the sheet due to slightly insufficient kneading. ×: Insufficient kneading at all, and the sheet has holes everywhere.
【0028】(4)熱的安定性 塩化ビニル系樹脂100重量部に有機錫系安定剤0.5
重量部、脂肪酸エステル系滑剤0.1重量部、ポリエチ
レン系滑剤0.2重量部を添加し十分撹拌混合した後、
この混合物60g(平均重合度1300タイプの塩化ビ
ニル系樹脂を用いた組成物)または62g(平均重合度
1000タイプの塩化ビニル系樹脂を用いた組成物)を
ラボプラストミル試験機(東洋精機(株)製)に投入
し、ローターの回転数50rpm、チャンバー温度18
0℃の条件下で、塩化ビニル系樹脂組成物を投入してか
らトルクが立ち上がりを示すまでの時間を測定した。こ
の時間が長いほど熱的安定性は高いと判断した。(4) Thermal stability 100 parts by weight of vinyl chloride resin and 0.5 parts of organotin stabilizer
Parts by weight, 0.1 part by weight of a fatty acid ester-based lubricant, and 0.2 parts by weight of a polyethylene-based lubricant, and after sufficiently stirring and mixing,
60 g of this mixture (composition using a vinyl chloride resin having an average degree of polymerization of 1300 type) or 62 g (composition using a vinyl chloride resin having an average degree of polymerization of 1000 type) was used as a laboplast mill tester (Toyo Seiki Co., Ltd.) )), The rotor rotation speed is 50 rpm, and the chamber temperature is 18
Under the condition of 0 ° C., the time from the introduction of the vinyl chloride resin composition to the rise of the torque was measured. The longer this time, the higher the thermal stability.
【0029】(5)スケール付着性 撹拌機を付設した内容積2000Lのステンレス製重合
器の内壁に初期1バッチのみ公知のスケール防止剤を塗
布して、本検討で実施した重合を連続10バッチ行った
後の内壁に付着したスケール状態を目視で確認し、スケ
ール付着状態を以下の評価基準にしたがって三段階で評
価した。 ○…重合容器内壁にスケールがほとんど付着していな
い。 △…重合容器内壁にスケールが少量付着し壁面が見えな
い。 ×…重合容器内壁にスケールが多量に付着している。(5) Scale Adhesion A known scale inhibitor was applied to the inner wall of a 2,000-L stainless steel polymerization vessel equipped with a stirrer in the initial batch, and the polymerization performed in this study was continuously performed for 10 batches. After that, the scale state adhered to the inner wall was visually checked, and the scale adhered state was evaluated in three steps according to the following evaluation criteria. …: Scale hardly adhered to the inner wall of the polymerization vessel. Δ: A small amount of scale adhered to the inner wall of the polymerization vessel, and the wall was not visible. X: A large amount of scale adhered to the inner wall of the polymerization vessel.
【0030】実施例1および3 撹拌機を付設した内容積2000Lのステンレス製重合
器内に、公知のスケール防止剤を塗布した後、鹸化度が
74%、平均重合度が2000であるPVA(以下、
「PVA(a)」という)の3重量%水溶液7.33k
g、鹸化度が56%、平均重合度が300であるPVA
(以下、「PVA(b)」という)0.165kg、
0.5%酢酸に0.5重量%濃度に溶解したキトサン溶
液1.1kg、およびジ−2−エチルヘキシルパーオキ
シジカーボネートを濃度70%で溶解したイソパラフィ
ン溶液0.393kgを仕込んだ。PVA(a)、PV
A(b)、0.5%酢酸に対し0.5重量%濃度に溶解
したキトサン溶液、およびジ−2−エチルヘキシルパー
オキシジカーボネートの仕込み量は塩化ビニル系単量体
100重量部に対してそれぞれ、0.04、0.03、
0.01、および0.05重量部とした。Examples 1 and 3 A well-known anti-scale agent was applied to a 2000 L stainless steel polymerization vessel equipped with a stirrer, and then PVA having a saponification degree of 74% and an average polymerization degree of 2000 (hereinafter referred to as PVA). ,
7.33k of a 3% by weight aqueous solution of "PVA (a)")
g, PVA having a saponification degree of 56% and an average polymerization degree of 300
(Hereinafter referred to as “PVA (b)”) 0.165 kg,
1.1 kg of a chitosan solution having a concentration of 0.5% by weight dissolved in 0.5% acetic acid and 0.393 kg of an isoparaffin solution having a concentration of 70% of di-2-ethylhexylperoxydicarbonate were charged. PVA (a), PV
A (b), the amount of the chitosan solution dissolved at a concentration of 0.5% by weight with respect to 0.5% acetic acid, and the charged amount of di-2-ethylhexyl peroxydicarbonate were 100 parts by weight of the vinyl chloride monomer. 0.04, 0.03, respectively
0.01 and 0.05 parts by weight.
【0031】重合器を密閉した後、内部を真空ポンプで
脱気し、次いで塩化ビニル単量体550kgおよび脱気
後60℃に温度調節した温水725kgを順次仕込ん
だ。この際塩化ビニル単量体の仕込み開始と同時に撹拌
機を稼働した。次いで外部ジャケットにより重合器内温
を実施例1では51.5℃、実施例3では57℃に昇温
後この温度に維持し、重合器内圧が定常圧より98.0
7kPa低下した時点で重合反応を停止し、未反応単量
体を回収して重合反応を終了した。得られたスラリーを
脱水、乾燥して実施例1では平均重合度1300タイ
プ、実施例3では平均重合度1000タイプの2種の塩
化ビニル樹脂を得、平均粒子径・粒度分布・多孔度の各
種特性値の測定に供した。After the polymerization vessel was sealed, the inside was degassed with a vacuum pump, and then 550 kg of vinyl chloride monomer and 725 kg of hot water adjusted to 60 ° C. after degassing were sequentially charged. At this time, the stirrer was operated simultaneously with the start of the charging of the vinyl chloride monomer. Next, the internal temperature of the polymerization reactor was raised to 51.5 ° C. in Example 1 and 57 ° C. in Example 3 by using an external jacket, and maintained at this temperature.
When the pressure decreased by 7 kPa, the polymerization reaction was stopped, unreacted monomers were recovered, and the polymerization reaction was terminated. The obtained slurry was dehydrated and dried to obtain two types of vinyl chloride resins having an average degree of polymerization of 1300 in Example 1 and an average degree of polymerization of 1000 in Example 3, and having various average particle diameter, particle size distribution and porosity. It was used for measurement of characteristic values.
【0032】さらに、得られた塩化ビニル樹脂200g
にメチルスズメルカプト安定剤1g、ペンタエリスリト
ール系滑剤0.2gおよびポリエチレン系滑剤0.4g
を添加し、十分撹拌混合して組成物を得、加工性・熱的
安定性の評価に供した。Further, 200 g of the obtained vinyl chloride resin
1 g of methyltin mercapto stabilizer, 0.2 g of pentaerythritol-based lubricant and 0.4 g of polyethylene-based lubricant
Was added and sufficiently stirred and mixed to obtain a composition, which was used for evaluation of processability and thermal stability.
【0033】実施例2および4 PVA(a)、PVA(b)、0.5重量%キトサン−
0.5%酢酸水溶液、およびジ−2−エチルヘキシルパ
ーオキシジカーボネートの仕込み量を塩化ビニル系単量
体100重量部に対してそれぞれ、0.02、0.0
1、0.1、および0.05重量部とした。それ以外は
実施例1および3と同様とし、実施例2では平均重合度
1300タイプ、実施例4では平均重合度1000タイ
プの2種の塩化ビニル樹脂および組成物を得、各種特性
値の測定、加工性評価・熱的安定性評価の評価に供し
た。Examples 2 and 4 PVA (a), PVA (b), 0.5% by weight chitosan
The charged amounts of the 0.5% acetic acid aqueous solution and di-2-ethylhexyl peroxydicarbonate were 0.02 and 0.02, respectively, based on 100 parts by weight of the vinyl chloride monomer.
1, 0.1 and 0.05 parts by weight. Except for this, the same procedures as in Examples 1 and 3 were carried out. In Example 2, two types of vinyl chloride resins and compositions having an average degree of polymerization of 1300 were obtained, and in Example 4, an average degree of polymerization of 1,000 was obtained. It was used for evaluation of processability evaluation and thermal stability evaluation.
【0034】比較例1 分散剤としてPVA(a)の3重量%水溶液9.99k
g(塩化ビニル系単量体100重量部に対して0.05
5重量部)および分子量450万のポリエチレンオキサ
イド(以下、「PEO」という)の0.5重量%水溶液
2.2kg(塩化ビニル系単量体100重量部に対して
0.002重量部)の2種のみを用い、実施例1と同様
にして平均重合度1300タイプの塩化ビニル樹脂およ
び組成物を得、各種特性値の測定、加工性評価・熱的安
定性評価の評価に供した。COMPARATIVE EXAMPLE 1 A 3% by weight aqueous solution of PVA (a) as a dispersant, 9.99 k
g (0.05 parts by weight per 100 parts by weight of vinyl chloride monomer)
2.2 kg of a 0.5% by weight aqueous solution of polyethylene oxide having a molecular weight of 4.5 million (hereinafter referred to as “PEO”) (0.002 parts by weight per 100 parts by weight of vinyl chloride monomer) Using only the seeds, a vinyl chloride resin and a composition having an average degree of polymerization of 1300 type were obtained in the same manner as in Example 1, and subjected to measurement of various characteristic values, evaluation of workability and evaluation of thermal stability.
【0035】比較例2 分散剤にPVA(a)として鹸化度が80%、平均重合
度が2000であるPVAの3重量%水溶液9.81k
g(塩化ビニル系単量体100重量部に対して0.05
4重量部)、PVA(b)として鹸化度が88%、平均
重合度が2300であるPVAの3重量%水溶液2.2
kg(塩化ビニル系単量体100重量部に対して0.0
12重量部)、およびPEOの0.5重量%水溶液5.
5kg(塩化ビニル系単量体100重量部に対して0.
005重量部)の3種のみを用いた以外は実施例3と同
様にして平均重合度1000タイプの塩化ビニル樹脂お
よび組成物を得、各種特性値の測定、加工性評価・熱的
安定性評価の評価に供した。Comparative Example 2 As a dispersant, PVA (a) was used as a PVA (a) having a saponification degree of 80% and an average degree of polymerization of 2000.
g (0.05 parts by weight per 100 parts by weight of vinyl chloride monomer)
4 parts by weight), and a 3% by weight aqueous solution of PVA having a degree of saponification of 88% and an average degree of polymerization of 2,300 as PVA (b) 2.2.
kg (0.0 to 100 parts by weight of vinyl chloride monomer)
12 parts by weight) and a 0.5% by weight aqueous solution of PEO.
5 kg (0.1 parts by weight per 100 parts by weight of vinyl chloride monomer)
005 parts by weight), except that a vinyl chloride resin and a composition having an average degree of polymerization of 1000 were obtained in the same manner as in Example 3 except that only three kinds were used, and measurement of various characteristic values, evaluation of processability and evaluation of thermal stability For evaluation.
【0036】比較例3 PVA(a)として鹸化度が88%、平均重合度が20
00であるPVAを用い、キトサン溶液の代わりにPE
Oを用いた以外は実施例1と同様にして平均重合度13
00タイプの塩化ビニル樹脂および組成物を得、各種特
性値の測定、加工性評価・熱的安定性評価の評価に供し
た。Comparative Example 3 PVA (a) had a saponification degree of 88% and an average polymerization degree of 20
Using PVA which is 00 and PE instead of chitosan solution
Except for using O, the average degree of polymerization was 13 in the same manner as in Example 1.
A 00 type vinyl chloride resin and composition were obtained, and were subjected to measurement of various characteristic values, evaluation of processability and evaluation of thermal stability.
【0037】評価結果をまとめて表1に示す。Table 1 summarizes the evaluation results.
【0038】[0038]
【表1】 [Table 1]
【0039】[0039]
【発明の効果】本発明により、重合時のスケール付着が
少なく加工性および熱的安定性に優れかつ物性低下のな
い塩化ビニル系樹脂の重合を行うことが可能である。し
たがって本発明の工業的価値はきわめて大きいものであ
る。According to the present invention, it is possible to carry out polymerization of a vinyl chloride resin having little scale adhesion during polymerization and excellent in processability and thermal stability and without deterioration in physical properties. Therefore, the industrial value of the present invention is extremely large.
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Claims (3)
量体と共重合可能な単量体と塩化ビニル単量体との混合
物を水性媒体中で懸濁重合させる際に、塩化ビニル単量
体、または塩化ビニル単量体と共重合可能な単量体と塩
化ビニル単量体との混合物に対し、懸濁分散剤として、
(a)鹸化度が70〜85%、平均重合度が1500〜
2500である部分鹸化ポリ酢酸ビニル、(b)鹸化度
が33〜70%、平均重合度が200〜1000である
部分鹸化ポリ酢酸ビニル、および(c)キトサンの有機
酸水溶液を用いることを特徴とする塩化ビニル系樹脂の
製造法。When a vinyl chloride monomer or a mixture of a vinyl chloride monomer and a monomer copolymerizable with the vinyl chloride monomer is subjected to suspension polymerization in an aqueous medium, a vinyl chloride monomer Body, or a mixture of a monomer copolymerizable with a vinyl chloride monomer and a vinyl chloride monomer, as a suspending dispersant,
(A) The degree of saponification is 70 to 85%, the average degree of polymerization is 1500 to
(B) partially saponified polyvinyl acetate having a saponification degree of 33 to 70% and an average degree of polymerization of 200 to 1000; and (c) an aqueous solution of chitosan in an organic acid. Manufacturing method of vinyl chloride resin.
量体と共重合可能な単量体と塩化ビニル単量体との混合
物100重量部に対し、懸濁分散剤として、前記(a)
を0.02〜0.08重量部、前記(b)を0.01〜
0.05重量部、および前記(c)を0.005〜0.
2重量部用いることを特徴とする請求項1記載の塩化ビ
ニル系樹脂の製造法。2. A suspension and dispersant for 100 parts by weight of a vinyl chloride monomer or a mixture of a vinyl chloride monomer and a monomer copolymerizable with the vinyl chloride monomer, wherein
From 0.02 to 0.08 parts by weight, and (b) from 0.01 to
0.05 parts by weight, and 0.005 to 0.5 parts by weight of (c).
2. The method for producing a vinyl chloride resin according to claim 1, wherein 2 parts by weight are used.
量体と共重合可能な単量体と塩化ビニル単量体との混合
物100重量部に対し、懸濁分散剤として、前記
(a)、(b)および(c)を、(a)/(b)=1/
1〜5/1の比率で(a)+(b)の合計部数が0.0
2〜0.08重量部、(a+b)/(c)=1/10〜
10/1の比率で(c)を0.005〜0.2重量部用
いることを特徴とする請求項1記載の塩化ビニル系樹脂
の製造法。3. A suspension and dispersant for 100 parts by weight of a vinyl chloride monomer or a mixture of a vinyl chloride monomer and a monomer copolymerizable with the vinyl chloride monomer, , (B) and (c) by (a) / (b) = 1 /
The total number of copies of (a) + (b) is 0.0 at a ratio of 1 to 5/1.
2 to 0.08 parts by weight, (a + b) / (c) = 1/10
2. The method for producing a vinyl chloride resin according to claim 1, wherein 0.005 to 0.2 parts by weight of (c) is used in a ratio of 10/1.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP11112878A JP2000302805A (en) | 1999-04-20 | 1999-04-20 | Manufacture of vinyl chloride resin |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP11112878A JP2000302805A (en) | 1999-04-20 | 1999-04-20 | Manufacture of vinyl chloride resin |
Publications (1)
Publication Number | Publication Date |
---|---|
JP2000302805A true JP2000302805A (en) | 2000-10-31 |
Family
ID=14597803
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP11112878A Pending JP2000302805A (en) | 1999-04-20 | 1999-04-20 | Manufacture of vinyl chloride resin |
Country Status (1)
Country | Link |
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JP (1) | JP2000302805A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR20170032183A (en) | 2015-09-14 | 2017-03-22 | 주식회사 엘지화학 | Vinyl chloride-vinyl acetate copolymer and preparation method thereof |
-
1999
- 1999-04-20 JP JP11112878A patent/JP2000302805A/en active Pending
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR20170032183A (en) | 2015-09-14 | 2017-03-22 | 주식회사 엘지화학 | Vinyl chloride-vinyl acetate copolymer and preparation method thereof |
US10093760B2 (en) | 2015-09-14 | 2018-10-09 | Lg Chem, Ltd. | Vinyl chloride-vinyl acetate copolymer and method of preparing the same |
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