JPH0859877A - Expandable as resin particle and heat-insulation material - Google Patents
Expandable as resin particle and heat-insulation materialInfo
- Publication number
- JPH0859877A JPH0859877A JP22571194A JP22571194A JPH0859877A JP H0859877 A JPH0859877 A JP H0859877A JP 22571194 A JP22571194 A JP 22571194A JP 22571194 A JP22571194 A JP 22571194A JP H0859877 A JPH0859877 A JP H0859877A
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- Japan
- Prior art keywords
- resin
- weight
- particles
- foaming agent
- content
- 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.)
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Landscapes
- Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】この発明は、ＡＳ樹脂製の発泡性
粒子と、ＡＳ樹脂製の断熱材とに関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to expandable particles made of AS resin and a heat insulating material made of AS resin.
【０００２】[0002]
【従来の技術】ポリスチレンを代表物とするスチレン系
樹脂が発泡体を作るのに適していることは広く知られて
いる。スチレン系樹脂の中でＡＳ樹脂、すなわちアクリ
ロニトリルとスチレンとの共重合樹脂は、ポリスチレン
と同様に発泡させて発泡体とすることができると考えら
れて来た。しかし、ＡＳ樹脂は、ポリスチレンに比べる
と、実用に供し得るような発泡体を作ることが遙かに困
難である。2. Description of the Related Art It is widely known that styrenic resins represented by polystyrene are suitable for forming foams. Among styrene resins, it has been considered that an AS resin, that is, a copolymer resin of acrylonitrile and styrene, can be foamed in the same manner as polystyrene. However, as compared with polystyrene, AS resin is much more difficult to make a foam that can be put to practical use.
【０００３】ＡＳ樹脂は、アクリロニトリル（以下、こ
れをＡＮと略称する）とスチレン（以下、これをＳＴと
略称する）とを共重合させることによって作られる。と
ころが、ＡＮとＳＴとはこれを任意の割合で共重合させ
ることが容易でない。このために、ＡＳ樹脂としては、
ＡＮの含有量の低いもの、例えばＡＮ含有量が２８重量
％以下のものが市販されているだけで、ＡＮ含有量が３
０重量％以上のＡＳ樹脂はまだ市販されるに至っていな
い。The AS resin is produced by copolymerizing acrylonitrile (hereinafter abbreviated as AN) and styrene (hereinafter abbreviated as ST). However, it is not easy to copolymerize AN and ST at an arbitrary ratio. For this reason, AS resin is
If the AN content is low, for example, the AN content is 28% by weight or less, the AN content is 3 or less.
0% by weight or more of AS resin has not been marketed yet.
【０００４】また、一般にＡＮ含有量の高いＡＳ樹脂を
作ろうとすると、得られるＡＳ樹脂は分子量の低いもの
になってしまう。従って、通常の重合方法によってＡＮ
含有量が２８重量％以上のＡＳ樹脂を作ろうとすると、
得られたＡＳ樹脂は分子量が低くて発泡に適したものに
ならない。だから、ＡＮ含有量が３０重量％以上で、且
つ発泡して実用に供し得るようなＡＳ樹脂を作ることは
容易でない。従って、ＡＮ含有量が３０重量％以上のＡ
Ｓ樹脂を使用して、これを実用に供し得るような発泡体
とするには、ＡＳ樹脂としてどのような性質が必要であ
るかが全く知られていなかった。Further, generally, when an AS resin having a high AN content is produced, the obtained AS resin has a low molecular weight. Therefore, by conventional polymerization methods, AN
When trying to make an AS resin with a content of 28% by weight or more,
The obtained AS resin has a low molecular weight and is not suitable for foaming. Therefore, it is not easy to make an AS resin having an AN content of 30% by weight or more and which can be foamed and put into practical use. Therefore, A with an AN content of 30% by weight or more
It has not been known at all what properties are required for the AS resin in order to use the S resin and make it into a foam that can be put to practical use.
【０００５】例えば、特開昭６１−１６９３５号公報
は、ＡＳ樹脂の高発泡体とその製造方法とを記載してい
る。この公報は、その中で独立気泡率が高く高倍率の発
泡体を得ようとする場合には、ＡＳ樹脂としてＡＮ含有
量が１０〜５０重量％、とりわけ２０〜３０重量％のも
のを用い、０．５ｇ／ｄｌの濃度のメチルエチルケトン
溶液の還元粘度が０．３〜１．０ｄｌ／ｇの範囲内にあ
るものを使用することを提唱している。ここで云う還元
粘度は、ＡＳ樹脂の分子量又は重合度を規定しているよ
うにも見えるが、還元粘度という概念自体が特殊なもの
であるために、その実体がよくわからない。また、上記
公報の実施例ではＡＮ含有量が２５重量％と２９重量％
のものについて記載しているだけで、３０重量％以上の
ものを記載していない。従って、この公報もＡＳ樹脂を
発泡させるには、どのような性質が必要であるかを教え
るに至っていない。For example, Japanese Patent Application Laid-Open No. 61-16935 describes a highly foamed AS resin and a method for producing the same. In this publication, in order to obtain a foam having a high closed cell ratio and a high expansion ratio, an AS resin having an AN content of 10 to 50% by weight, particularly 20 to 30% by weight, is used. It is proposed to use a methyl ethyl ketone solution having a concentration of 0.5 g / dl and a reduced viscosity in the range of 0.3 to 1.0 dl / g. The reduced viscosity referred to here seems to regulate the molecular weight or the degree of polymerization of the AS resin, but its concept is not clear because the concept of reduced viscosity itself is special. In the examples of the above publications, the AN content is 25% by weight and 29% by weight.
However, the above description does not describe 30% by weight or more. Therefore, this publication also fails to teach what kind of properties are required to foam the AS resin.
【０００６】また、特開平１−２７２６４２号公報は、
ＡＳ樹脂製の発泡性粒子を製造する方法を記載してい
る。この公報は、ＡＮが１５〜３５重量％含まれている
ＡＳ樹脂を用いるように記載しているが、ＡＳ樹脂を発
泡させるにはそれ以外にどのような性質が必要であるか
を全く教えていない。Further, Japanese Patent Laid-Open No. 1-272642 discloses that
A method for producing expandable particles made of AS resin is described. This publication describes using an AS resin containing 15 to 35% by weight of AN, but does not teach what other properties are necessary for foaming the AS resin. Absent.
【０００７】[0007]
【発明が解決しようとする課題】この発明者は、ＡＮ含
有量が３０重量％以上のＡＳ樹脂はまだ市販されていな
いという実情、及び３０重量％以上のＡＮ含有量を持っ
たＡＳ樹脂を従来の方法で製造したのでは、分子量が小
さくなって発泡体として実用に適したものにならないと
いう実情に鑑み、２５重量％以上のＡＮを含み、且つ発
泡して実用に供し得るような物性を持ったＡＳ樹脂発泡
体を得ようと企てた。この発明は、このような目的をも
ってなされたものである。The present inventor has found that AS resins having an AN content of 30% by weight or more have not been marketed yet and that AS resins having an AN content of 30% by weight or more have been conventionally used. In view of the fact that the product produced by the method of 1) has a small molecular weight and is not suitable for practical use as a foam, it contains 25% by weight or more of AN and has physical properties such that it can be foamed and put into practical use. Attempted to obtain an AS resin foam. The present invention has been made with such a purpose.
【０００８】[0008]
【課題を解決するための手段】この発明者は、上記の課
題を解決するために、ＡＳ樹脂の製造経験を持った各方
面の技術者に、ＡＮ含有量が２５重量％以上であって、
充分な機械的強度を持った高分子量のＡＳ樹脂を製造す
るように、協力を依頼した。この発明者は、こうして提
供されたＡＳ樹脂に色々な発泡剤を含ませ、さらにこれ
を発泡させて得られた発泡体の物性を検討した。In order to solve the above-mentioned problems, the present inventor has advised engineers of various fields who have experience in producing AS resins that the AN content is 25% by weight or more,
Cooperation was requested to produce a high molecular weight AS resin with sufficient mechanical strength. The present inventor examined the physical properties of a foam obtained by allowing the AS resin thus provided to contain various foaming agents and further foaming the foamed agent.
【０００９】その結果、この発明者は、ＡＮ含有量が２
５〜５０重量％のＡＳ樹脂を材料として、これを発泡さ
せて発泡体を作り、この発泡体を実用に供し得るように
するためには、樹脂のメルトフローレートと樹脂の重量
平均分子量（以下ではこれを単に分子量という）とが重
要であることを見出した。すなわち、メルトフローレー
ト（以下、これをＭＦＲと略称する）が０．１〜２０ｇ
／１０分の範囲内にあること、及び分子量が２５，００
０以上であることが必要であることを見出した。このよ
うなＭＦＲと分子量とを持ったＡＳ樹脂を用いてこれを
発泡させると、得られた発泡体が実用に供し得るものに
なることを見出した。すなわち、このような樹脂はこれ
を加熱したときに発泡に適した粘度を示す温度範囲が比
較的広く、また発泡したのちには充分な機械的強度を示
すに至るものであることを確認した。As a result, the inventor has found that the AN content is 2
5 to 50 wt% of AS resin is used as a material to foam this to make a foam, and in order to make this foam usable for practical use, the melt flow rate of the resin and the weight average molecular weight of the resin (hereinafter Then, this is simply called the molecular weight) and was found to be important. That is, the melt flow rate (hereinafter, abbreviated as MFR) is 0.1 to 20 g.
/ 10 minutes and a molecular weight of 25,000
It has been found that it is necessary to be 0 or more. It has been found that, when an AS resin having such MFR and molecular weight is used for foaming, the obtained foam can be put to practical use. That is, it was confirmed that such a resin has a relatively wide temperature range in which it exhibits a viscosity suitable for foaming when it is heated, and exhibits sufficient mechanical strength after foaming.
【００１０】また、上述のようなＡＳ樹脂に対しては、
発泡剤として沸点が−５０〜＋４０℃、溶解度パラメー
ター（以下、これをＳＰと略称する）が８．０〜１１．
０（ｃａｌ／ｃｍ3 ）1/2 （以下、このディメンション
を省略してＤで表す）のハロゲン化脂肪族炭化水素を用
いるのが好適であることを見出した。すなわち、上述の
ようなＡＳ樹脂には一般に発泡剤を含ませ難いものであ
るが、上述のような発泡剤を選んで用いると、含ませ難
いとは云っても含浸温度を高め含浸時間を長くすること
によって、比較的容易に含浸させ得ることを見出した。Further, for the AS resin as described above,
The foaming agent has a boiling point of −50 to + 40 ° C. and a solubility parameter (hereinafter, abbreviated as SP) of 8.0 to 11.
It has been found that it is preferable to use a halogenated aliphatic hydrocarbon of 0 (cal / cm 3 ) 1/2 (hereinafter, this dimension is omitted and represented by D). That is, although it is generally difficult to include a foaming agent in the AS resin as described above, if the foaming agent as described above is selected and used, the impregnation temperature is increased and the impregnation time is lengthened even if it is difficult to include the foaming agent. It was found that by doing so, the impregnation can be performed relatively easily.
【００１１】こうして得られた発泡剤含有ＡＳ樹脂は、
これを水蒸気に直接接触させて加熱すると、従来の発泡
性ポリスチレン粒子と同様に発泡して発泡体となる。従
って、この発泡剤含有ＡＳ樹脂はこれを発泡性粒子とし
て使用できる。その上に、こうして得られたＡＳ樹脂製
の発泡性粒子はこれまでに見られない長所を持つもので
あることが判明した。その長所とは発泡剤がＡＳ樹脂か
ら容易に揮散しないということであり、従ってポリスチ
レン製の発泡性粒子に比べると遙かに長い期間発泡性を
保持しているということであり、従って発泡性粒子とし
て長期間保存できるということである。The AS resin containing a foaming agent thus obtained is
When this is brought into direct contact with water vapor and heated, it expands into a foam similar to the conventional expandable polystyrene particles. Therefore, this blowing agent-containing AS resin can be used as expandable particles. In addition, it has been found that the AS resin expandable particles thus obtained have advantages not seen before. Its advantage is that the foaming agent does not easily volatilize from the AS resin, and therefore it retains its foamability for a much longer period than the expandable particles made of polystyrene. It means that it can be stored for a long time.
【００１２】さらにこの発明者は、上述のＡＳ樹脂製発
泡性粒子を１０〜５０倍に発泡させると、得られた発泡
体中に発泡剤が残留し、残留した発泡剤が揮散し難いた
めに長期にわたって発泡体中に残ることを見出し、さら
にこれによって好結果のもたらされることを見出した。
すなわち、上述の発泡剤はそれ自身が低い熱伝導率を持
つために、発泡体が断熱材としてとくにすぐれた性質を
発揮するに至ることを見出した。この発明は、このよう
な知見に基づいて完成されたものである。Furthermore, the present inventor expands the expandable particles made of AS resin 10 to 50 times, so that the foaming agent remains in the obtained foam and it is difficult for the remaining foaming agent to volatilize. It has been found that it remains in the foam for a long period of time, and that this is successful.
That is, it has been found that the above-mentioned foaming agent itself has a low thermal conductivity, so that the foam exhibits particularly excellent properties as a heat insulating material. The present invention has been completed based on such knowledge.
【００１３】この発明は、一面ではＡＳ樹脂製の発泡性
粒子を提供するものであり、他面では上記ＡＳ樹脂製の
発泡性粒子を加熱して発泡させた発泡体を提供するもの
である。前者の発泡性粒子は発泡剤が永く樹脂中に残留
するために長期の保存に耐えてよく発泡するという特性
を示し、後者の発泡体は、熱伝導率の低い発泡剤が長期
にわたって残留するために、長期にわたって断熱性が良
好である、という特性を示すものである。In one aspect, the present invention provides expandable particles made of AS resin, and in another aspect, it provides a foam obtained by heating the expandable particles made of AS resin to expand. The former expandable particles show the property that the foaming agent remains in the resin for a long time, and therefore it can withstand long-term storage and foams well, while the latter foaming agent has a low thermal conductivity because the foaming agent remains for a long time. In addition, it has a characteristic that the heat insulating property is good for a long period of time.
【００１４】上記の発泡性粒子に関する発明は、ＡＮ含
有量が２５〜５０重量％のＡＳ樹脂で、ＭＦＲが０．１
〜２０ｇ／１０分、分子量が２５，０００以上のＡＳ樹
脂に、沸点が−５０〜＋４０℃、ＳＰが８．０〜１１．
０Ｄのハロゲン化脂肪族炭化水素を含ませることを特徴
としている。The invention relating to the expandable particles is an AS resin having an AN content of 25 to 50% by weight and an MFR of 0.1.
˜20 g / 10 minutes, AS resin having a molecular weight of 25,000 or more, boiling point of −50 to + 40 ° C., SP of 8.0 to 11.
It is characterized by containing 0D halogenated aliphatic hydrocarbon.
【００１５】また、上記の断熱材に関する発明は、ＡＮ
含有量が２５〜５０重量％のＡＳ樹脂で、ＭＦＲが０．
１〜２０ｇ／１０分、分子量が２５，０００以上のＡＳ
樹脂に、沸点が−５０〜＋４０℃、ＳＰが８．０〜１
１．０Ｄのハロゲン化脂肪族炭化水素を含ませたＡＳ樹
脂製発泡性粒子を加熱して発泡させるとともに互いに融
着させ、発泡倍率を１０〜５０倍の成形体としたことを
特徴とするものである。The invention relating to the above heat insulating material is AN
An AS resin having a content of 25 to 50% by weight and an MFR of 0.
AS of 1 to 20 g / 10 minutes and molecular weight of 25,000 or more
The resin has a boiling point of -50 to + 40 ° C and an SP of 8.0 to 1
A molded article having a foaming ratio of 10 to 50 times, which is obtained by heating AS resin expandable particles containing 1.0 D halogenated aliphatic hydrocarbon to be foamed and fused to each other. Is.
【００１６】この発明では、ＡＳ樹脂を用いるが、その
樹脂はＡＮ含有量が２５〜５０重量％であって、ＭＦＲ
が０．１〜２０ｇ／１０分、分子量が２５，０００以上
のものである。このＡＳ樹脂は、試作されただけで、ま
だ広く市販されるに至っていない。この発明者は、他の
者からこのＡＳ樹脂の提供を受けたので、樹脂の製造方
法の詳しいことは知らない。In the present invention, an AS resin is used, and the resin has an AN content of 25 to 50% by weight and has an MFR of
Of 0.1 to 20 g / 10 minutes and a molecular weight of 25,000 or more. This AS resin has just been prototyped and has not yet been widely marketed. Since the present inventor has received this AS resin from another person, he does not know the details of the method for producing the resin.
【００１７】この発明者は、ＡＳ樹脂のＡＮ含有量、Ｍ
ＦＲ及び分子量を次の方法によって測定した。 ＡＮ含有量の測定方法 ： 赤外吸収スペクトル法 ＭＦＲの測定条件 ： 温度２３０℃、荷重２．１
６ｋｇ 分子量の測定方法 ： ＧＰＣ法The inventor has found that the AN content of AS resin, M
FR and molecular weight were measured by the following methods. Method for measuring AN content: Infrared absorption spectrum method Measurement conditions for MFR: Temperature 230 ° C., load 2.1
6 kg molecular weight measurement method: GPC method
【００１８】この発明において、ＡＮ含有量を２５〜５
０重量％の範囲内に限定した理由は、ＡＮ含有量が２５
重量％未満では発泡剤を長期にわたって保留する効果に
乏しいからであり、逆にＡＮ含有量が５０重量％を越え
ると、発泡剤を含浸させることが困難となるからであ
る。In the present invention, the AN content is 25 to 5
The reason for limiting the content within the range of 0% by weight is that the AN content is 25
This is because if it is less than wt%, the effect of retaining the foaming agent for a long time is poor, and conversely if the AN content exceeds 50 wt%, it becomes difficult to impregnate the foaming agent.
【００１９】また、この発明において、ＭＦＲを０．１
〜２０ｇ／１０分の範囲内に限定した理由は、樹脂がそ
の範囲内の溶融粘度を持たないと、これに発泡剤を含ま
せて加熱して発泡させようとしたとき、発泡に適した粘
度を樹脂に持たせることができないからである。例え
ば、ＭＦＲが０．１より小さくなると、発泡時に樹脂の
粘度が下がりにくく、従って発泡倍率を高くすることが
できないからであり、また逆にＭＦＲが２０より大きく
なると、発泡時に樹脂の粘度低下が著しく、気泡が生成
されにくくなり、従って発泡倍率を上げることができな
いからである。例えば、ＡＮ含有量が４０重量％のＡＳ
樹脂を用い、これに発泡剤としてＣＨ2 ＦＣＦ3 のハロ
ゲン化炭化水素を含ませ、得られた発泡性粒子を加熱発
泡させた場合、ＭＦＲと発泡倍率とは、下記表１に示し
たような関係になったからである。In the present invention, the MFR is 0.1
The reason for limiting to within the range of 20 g / 10 min is that if the resin does not have a melt viscosity within the range, a viscosity suitable for foaming is obtained when the resin is mixed with a foaming agent and heated to foam. This is because the resin cannot have. For example, when the MFR is less than 0.1, the viscosity of the resin is less likely to decrease during foaming, and therefore the expansion ratio cannot be increased. On the contrary, when the MFR is greater than 20, the viscosity of the resin decreases during foaming. This is because bubbles are significantly less likely to be generated, and therefore the expansion ratio cannot be increased. For example, AS with an AN content of 40% by weight
When a resin is used, which contains a halogenated hydrocarbon of CH 2 FCF 3 as a foaming agent and the resulting expandable particles are thermally foamed, the MFR and the expansion ratio are as shown in Table 1 below. Because it became a relationship.
【００２０】[0020]
【表１】ＭＦＲと発泡倍率との関係 ＭＦＲ（ｇ／１０分） 発泡倍率 ０．０５ １２倍 ０．１ ２５倍 ０．５ ４５倍 １．０ ６０倍 ５．０ ８５倍 １０．０ ８９倍 １５．０ ６２倍 ２０．０ ５０倍 ２５．０ ２０倍[Table 1] Relationship between MFR and expansion ratio MFR (g / 10 min) Expansion ratio 0.05 12 times 0.1 25 times 0.5 45 times 1.0 60 times 5.0 85 times 10.0 89 times 15.0 62 times 20.0 50 times 25.0 20 times
【００２１】また、ＭＦＲを０．１〜２０ｇ／１０分の
範囲内に限定した理由は、発泡性粒子の成形性にも由来
している。すなわち、上記の発泡剤ＣＨ2 ＦＣＦ3 を含
んだＡＮ含有量４０重量％の発泡性粒子を加熱して、２
０倍に発泡させた予備発泡粒子を作り、これを金型に入
れて再び水蒸気で加熱して発泡成形体としたとき、得ら
れた発泡成形体における粒子の伸びと融着性とを検討し
た結果、ＭＦＲが０．１〜２０ｇ／１０分の範囲内のも
のは一応粒子の伸びも融着性も良好であったが、０．１
ｇ未満のものは伸びも融着も悪く、２０ｇを越えるもの
は発泡体の表面が溶解してしまうからである。The reason why the MFR is limited within the range of 0.1 to 20 g / 10 minutes is also derived from the moldability of the expandable particles. That is, the expandable particles containing 40% by weight of AN containing the above foaming agent CH 2 FCF 3 are heated to
When pre-expanded particles that were expanded 0 times were prepared, and when they were placed in a mold and heated again with steam to form a foamed molded product, the expansion and fusion property of the particles in the resulting foamed molded product were examined. As a result, when the MFR was in the range of 0.1 to 20 g / 10 min, the elongation and the fusion property of the particles were good, but 0.1
This is because if it is less than g, the elongation and fusion are poor, and if it exceeds 20 g, the surface of the foam is dissolved.
【００２２】ＡＳ樹脂に発泡剤を含浸させて発泡性粒子
を作るには、ポリスチレンを材料としてこれに発泡剤を
含浸させる方法がそのまま採用できる。すなわち、ＡＳ
樹脂の粒子を懸濁剤を含んだ水溶液中に分散させ、この
分散物をオートクレーブに入れて撹拌しながら、オート
クレーブ内に発泡剤を圧入してＡＳ樹脂に発泡剤を含浸
させて発泡性粒子とするのである。ＡＳ樹脂は前述のよ
うに発泡剤を含浸させ難いので、分散物の温度を高め、
圧入に長時間をかけるという点で、ポリスチレン樹脂と
異なるだけである。In order to make the expandable particles by impregnating the AS resin with a foaming agent, the method of using polystyrene as a material and impregnating the foaming agent can be employed as it is. That is, AS
Resin particles are dispersed in an aqueous solution containing a suspending agent, the dispersion is put into an autoclave and stirred, and a foaming agent is pressed into the autoclave to impregnate the AS resin with the foaming agent to form foamable particles. To do. As described above, since it is difficult for the AS resin to impregnate the foaming agent, the temperature of the dispersion should be raised.
It is different from polystyrene resin only in that it takes a long time for press fitting.
【００２３】また、この発明では、ＡＳ樹脂の分子量を
２５，０００以上に限定したが、それは分子量が２５，
０００未満のＡＳ樹脂は、発泡成形時に樹脂の伸びが悪
かったり、融着性が悪かったりしたからである。例え
ば、ＡＮ含有量が４５重量％で、ＭＦＲが１．２ｇ／１
０分のＡＳ樹脂を用いて、これにＣＨ3 ＣＣｌＦ2 の発
泡剤を含ませて発泡性粒子を作り、これに水蒸気を接触
させて加熱し２５倍に発泡させた発泡成形体を作ったと
ころ、分子量が２０，０００のものでは樹脂の伸びも発
泡粒子の融着性も悪く、分子量２５，０００のもので伸
びが一応満足なものとなり融着性も良好となり、分子量
が４０，０００以上９０，０００までのものは何れも伸
びも融着性も良好となることを認めたからである。Further, in the present invention, the molecular weight of the AS resin is limited to 25,000 or more.
This is because the AS resin of less than 000 has a poor resin elongation and a poor fusion bonding property during foam molding. For example, the AN content is 45% by weight and the MFR is 1.2 g / 1.
When a foaming agent of CH 3 CClF 2 was added to an AS resin for 0 minutes to make expandable particles, steam was brought into contact with the expanded resin to heat it to form a foamed molded product 25 times When the molecular weight is 20,000, the elongation of the resin and the fusion property of the foamed particles are poor, and when the molecular weight is 25,000, the elongation is tentatively satisfactory and the fusion property becomes good, and the molecular weight is 40,000 or more 90. This is because it was confirmed that all of those up to 1,000 have good elongation and fusion.
【００２４】この発明では、発泡剤として沸点が−５０
〜＋４０℃、ＳＰが８．０〜１１．０Ｄのハロゲン化脂
肪族炭化水素を用いる。沸点が−５０〜＋４０℃の範囲
内であることを必要とする理由は、この範囲内にない
と、ＡＳ樹脂の加熱軟化時に、発泡剤がＡＳ樹脂中で気
化して一様な気泡を生成しないからである。In the present invention, the boiling point of the foaming agent is -50.
A halogenated aliphatic hydrocarbon having a temperature of + 40 ° C. and an SP of 8.0 to 11.0 D is used. The reason why the boiling point is required to be in the range of −50 to + 40 ° C. is that if it is not within this range, the foaming agent is vaporized in the AS resin to generate uniform bubbles when the AS resin is heated and softened. Because not.
【００２５】発泡剤のＳＰ値は、８．０〜１１．０Ｄの
範囲内になければならない。ここで、ＳＰ値はFedorsの
方法によって測定したがその詳細は次のとおりである。 ＳＰ値＝〔Σ△ｌｉ／Σ△Ｎｉ〕1/2 ここで、△ｌｉ（ｃａｌ／ｍｏｌ）は蒸発エネルギーで
あり、△Ｎｉ（ｃｍ3 ／ｍｏｌ）はモル体積である。The SP value of the blowing agent must be in the range of 8.0-11.0D. Here, the SP value was measured by the method of Fedors, and the details are as follows. SP value = [ΣΔli / ΣΔNi] 1/2 Here, Δli (cal / mol) is the evaporation energy, and ΔNi (cm 3 / mol) is the molar volume.
【００２６】発泡剤のＳＰ値が８．０〜１１．０Ｄの範
囲内になければならないとした理由は、発泡性粒子を加
熱して予備発泡粒子とし、この予備発泡粒子を金型に入
れて加熱し、粒子を発泡させるとともに融着させて発泡
成形体とした場合に、良好な成形体を得るために必要と
される発泡粒子の伸びと融着性とを綜合的に判断した結
果である。The reason why the SP value of the foaming agent must be in the range of 8.0 to 11.0D is that the expandable particles are heated to form pre-expanded particles, and the pre-expanded particles are put in a mold. It is the result of comprehensively judging the elongation and the fusion property of the expanded particles required to obtain a good molded product when the foamed molded product is obtained by heating and fusing and fusing the particles. .
【００２７】例えばＡＮ含有量が４２重量％で、分子量
が５５，０００、ＭＦＲが１．０ｇ／１０分のＡＳ樹脂
を用い、これに色々なＳＰ値のハロゲン化脂肪族炭化水
素を含ませて発泡性粒子を作り、得られた発泡性粒子を
最高倍率に発泡させて発泡倍率を計り、またこの発泡し
た粒子を金型に入れて２０倍に発泡した成形体を作り、
その成形体における樹脂の伸び、融着性などを検討して
成形性を綜合的に判断したところ、下記表２に示すよう
な結果が得られたからである。For example, an AS resin having an AN content of 42% by weight, a molecular weight of 55,000, and an MFR of 1.0 g / 10 min is used, which contains halogenated aliphatic hydrocarbons having various SP values. Make expandable particles, expand the obtained expandable particles to the maximum expansion ratio to measure the expansion ratio, and put the expanded particles in a mold to make a molded product expanded 20 times,
This is because the results shown in Table 2 below were obtained when the moldability was comprehensively judged by examining the elongation and fusion bondability of the resin in the molded product.
【００２８】[0028]
【表２】 [Table 2]
【００２９】[0029]
【発明の効果】この発明に係るＡＳ樹脂は、ＡＮ含有量
が２５〜５０重量％であり、ＭＦＲが０．１〜２０ｇ／
１０分で、分子量が２５，０００以上となっているの
で、一般のポリスチレンに比べると耐熱性が高く、ＡＳ
樹脂の中では加熱溶融時に発泡に適した粘度を示す温度
範囲が比較的広く、また機械的強度も充分で発泡体を作
るに適したものとなっている。また、発泡剤として沸点
が−５０〜＋４０℃、ＳＰ値が８．０〜１１．０Ｄのハ
ロゲン化脂肪族炭化水素を用いているので、上述のＡＳ
樹脂は一般に発泡剤を含浸させ難いものであるに拘わら
ず、この発泡剤はこれをＡＳ樹脂に比較的含浸させ易
く、またこの発泡剤はＡＳ樹脂を加熱したとき、ＡＳ樹
脂中で気化して樹脂中に気泡を生成し易く、従ってＡＳ
樹脂をよく発泡させる。しかも、この発泡剤はＡＳ樹脂
から揮散し難いので、発泡性粒子として永く貯蔵するこ
とができ、従って長期間保存して必要なときにこれを発
泡させて発泡体とすることができるので使用に便利であ
る。しかも、この発泡剤は、熱伝導率が小さいという特
性を持つところ、発泡後もＡＳ樹脂中に永く残留するの
で、得られた発泡体は断熱性の良好なものとなる。The AS resin according to the present invention has an AN content of 25 to 50% by weight and an MFR of 0.1 to 20 g /
Since the molecular weight is 25,000 or more in 10 minutes, it has higher heat resistance than general polystyrene and
Among resins, the temperature range in which a viscosity suitable for foaming when heated and melted is relatively wide, and the mechanical strength is sufficient, which makes it suitable for making foams. Further, since a halogenated aliphatic hydrocarbon having a boiling point of −50 to + 40 ° C. and an SP value of 8.0 to 11.0 D is used as the foaming agent, the above-mentioned AS is used.
Although the resin is generally difficult to be impregnated with the foaming agent, the foaming agent is relatively easy to impregnate the AS resin, and the foaming agent is vaporized in the AS resin when the AS resin is heated. Bubbles are easily generated in the resin and therefore AS
Allow the resin to foam well. Moreover, since this foaming agent does not easily volatilize from the AS resin, it can be stored as expandable particles for a long time, and therefore, it can be stored for a long period of time and foamed to form a foam when necessary. It is convenient. Moreover, since this foaming agent has a characteristic that the thermal conductivity is small, it remains in the AS resin for a long time even after foaming, so that the obtained foam has a good heat insulating property.
【００３０】とくに上記の発泡性粒子は、加熱されたと
き発泡に適した溶融粘度を示すから、これに水蒸気を接
触させて粒子を加熱して発泡粒子を作り、この発泡粒子
を金型に入れ金型内に水蒸気を吹き込んで粒子を加熱す
ると、金型内で粒子はさらに発泡するとともに互いに融
着しその結果希望する倍率に発泡した良好な発泡成形体
を生成する。こうして発泡倍率を１０〜５０倍に調整す
ると、得られた発泡体は断熱材として使用するに適した
ものとなる。しかも、この発泡体の中では熱伝導率の小
さい発泡剤が長期にわたって残留するので、この発泡体
は断熱性の良好なものとなる。この発明は、このような
利益を与えるものである。Particularly, the above-mentioned expandable particles have a melt viscosity suitable for foaming when heated, so that steam is brought into contact with the particles to heat the particles to form expanded particles, and the expanded particles are placed in a mold. When steam is blown into the mold to heat the particles, the particles are further foamed and fused to each other in the mold, and as a result, a good foamed molded product having a desired expansion ratio is produced. When the expansion ratio is adjusted to 10 to 50 times in this way, the obtained foam becomes suitable for use as a heat insulating material. Moreover, since the foaming agent having a small thermal conductivity remains in this foam for a long period of time, this foam has a good heat insulating property. The present invention provides such benefits.
【００３１】以下に実施例と比較例とを挙げてこの発明
のすぐれている所以を具体的に明らかにする。The advantages of the present invention will be specifically described below with reference to Examples and Comparative Examples.
【００３２】[0032]
【実施例１】ＡＮ含有量４０ｗｔ％のペレット状ＡＳ樹
脂１００重量部を５リットルオートクレーブに入れこれ
に水３００重量部と分散剤として酸化マグネシウム３重
量部とを加えて撹拌し水性分散物を作った。発泡剤とし
てＨＦＣ−１４２ｂ(CH3CClF2)（沸点−９．２℃、ＳＰ
値９．０Ｄ）４０重量部を圧入したのち、１２０℃まで
昇温し２４時間発泡剤の含浸を行った。その後、３０℃
まで冷却し取り出して発泡剤含有ＡＳ樹脂粒子を得た。Example 1 100 parts by weight of a pelletized AS resin having an AN content of 40 wt% was placed in a 5 liter autoclave, 300 parts by weight of water and 3 parts by weight of magnesium oxide as a dispersant were added and stirred to prepare an aqueous dispersion. It was HFC-142b (CH 3 CClF 2 ) ( boiling point -9.2 ° C. as a blowing agent, SP
After pressing in 40 parts by weight (value 9.0D), the temperature was raised to 120 ° C. and impregnation with the foaming agent was carried out for 24 hours. After that, 30 ℃
The mixture was cooled to the temperature and taken out to obtain foaming agent-containing AS resin particles.
【００３３】この樹脂粒子を１０℃の保冷庫で保管し、
熟成した後スチームによって２０倍に発泡した。約１日
発泡粒子を２０℃恒温室で放置した後、０．４ｋｇ／ｃ
ｍ2のスチームによって成形し成形品を得た。The resin particles are stored in a cold storage at 10 ° C,
After aging, it was foamed 20 times with steam. After leaving the foamed particles in a thermostatic chamber at 20 ° C for about 1 day, 0.4 kg / c
A molded product was obtained by molding with m 2 steam.
【００３４】成形品は外観・融着ともに良好であった。
この成形品中の発泡剤量と成形品の熱伝導率を経時をお
って測定した結果、表３のように発泡剤量・熱伝導率と
も非常に変化の小さい物であった。The molded product was good in both appearance and fusion.
As a result of measuring the amount of the foaming agent in this molded product and the thermal conductivity of the molded product over time, as shown in Table 3, both the amount of the foaming agent and the thermal conductivity were very small.
【００３５】[0035]
【表３】 [Table 3]
【００３６】[0036]
【実施例２】ＡＮ含有量３０ｗｔ％のＡＳ樹脂を用いた
以外は全て実施例１と同様の方法で含浸・発泡を行い、
２０倍の発泡粒子を得た。その発泡粒子を２０℃恒温室
で保管した後、０．５ｋｇ／ｃｍ2 のスチームで成形し
成形品を得た。この成形品も外観・融着ともに良好であ
った。実施例１と同様、発泡剤量と熱伝導率を測定した
結果、表４のように発泡剤量・熱伝導率とも非常に変化
の小さい物であった。Example 2 Impregnation and foaming were all carried out in the same manner as in Example 1 except that AS resin having an AN content of 30 wt% was used.
20 times the expanded particles were obtained. The foamed particles were stored in a thermostatic chamber at 20 ° C. and then molded with steam of 0.5 kg / cm 2 to obtain a molded product. The appearance and fusion of this molded product were also good. As in Example 1, the amount of the foaming agent and the thermal conductivity were measured. As a result, as shown in Table 4, both the amount of the foaming agent and the thermal conductivity were very small.
【００３７】[0037]
【表４】 [Table 4]
【００３８】[0038]
【実施例３】ＡＮ含有量５０ｗｔ％のＡＳ樹脂を用いた
以外は全て実施例１と同様の方法で含浸・発泡を行い、
２０倍の発泡粒子を得た。その発泡粒子を２０℃恒温室
で保管した後、０．２ｋｇ／ｃｍ2 のスチームで成形し
成形品を得た。この成形品も外観・融着ともに良好であ
った。実施例１と同様、発泡剤量と熱伝導率を測定した
結果、表５のように発泡剤量・熱伝導率とも非常に変化
の小さい物であった。Example 3 Impregnation and foaming were performed in the same manner as in Example 1 except that AS resin having an AN content of 50 wt% was used.
20 times the expanded particles were obtained. The foamed particles were stored in a thermostatic chamber at 20 ° C., and then molded with 0.2 kg / cm 2 steam to obtain a molded product. The appearance and fusion of this molded product were also good. As in Example 1, the amount of foaming agent and the thermal conductivity were measured. As a result, as shown in Table 5, the amount of foaming agent and the thermal conductivity were very small.
【００３９】[0039]
【表５】 [Table 5]
【００４０】[0040]
【実施例４】実施例１と同様の方法で含浸・発泡を行
い、３０倍の発泡粒子を得た。その発泡粒子を２０℃恒
温室で保管した後、０．３ｋｇ／ｃｍ2 のスチームで成
形し成形品を得た。この成形品も外観・融着ともに良好
であった。実施例１と同様、発泡剤量と熱伝導率を測定
した結果、表６のように発泡剤量・熱伝導率とも非常に
変化の小さい物であった。Example 4 Impregnation and foaming were carried out in the same manner as in Example 1 to obtain expanded particles 30 times. The foamed particles were stored in a thermostatic chamber at 20 ° C., and then molded with steam of 0.3 kg / cm 2 to obtain a molded product. The appearance and fusion of this molded product were also good. As in Example 1, the amount of the foaming agent and the thermal conductivity were measured. As a result, as shown in Table 6, the amount of the foaming agent and the thermal conductivity were very little changed.
【００４１】[0041]
【表６】 [Table 6]
【００４２】[0042]
【実施例５】実施例１と同様の方法で含浸・発泡を行
い、４０倍の発泡粒子を得た。その発泡粒子を２０℃恒
温室で保管した後、０．２ｋｇ／ｃｍ2 のスチームで成
形し成形品を得た。この成形品も外観・融着ともに良好
であった。実施例１と同様、発泡剤量と熱伝導率を測定
した結果、表７のように発泡剤量・熱伝導率とも非常に
変化の小さい物であった。[Example 5] Impregnation and foaming were carried out in the same manner as in Example 1 to obtain 40-fold expanded particles. The foamed particles were stored in a thermostatic chamber at 20 ° C., and then molded with 0.2 kg / cm 2 steam to obtain a molded product. The appearance and fusion of this molded product were also good. As in Example 1, the amount of the foaming agent and the thermal conductivity were measured. As a result, as shown in Table 7, both the amount of the foaming agent and the thermal conductivity were very small.
【００４３】[0043]
【表７】 [Table 7]
【００４４】[0044]
【実施例６】ＡＮ含有量４０ｗｔ％のＡＳ樹脂１００重
量部を５リットルオートクレーブに入れ、これに水３０
０重量部と分散剤として酸化マグネシウム２．５重量部
とを加えて撹拌し分散させた。発泡剤としてＨＦＣ−１
３４ａ(CH2FCF3) （沸点−２６．１℃、ＳＰ値８．７
Ｄ）４０重量部を圧入したのち、９５℃まで昇温し４８
時間含浸を行った。その後、３０℃まで冷却し取り出し
て発泡剤含有ＡＳ樹脂粒子を得た。Example 6 100 parts by weight of AS resin having an AN content of 40 wt% was placed in a 5 liter autoclave, and water 30 was added thereto.
0 parts by weight and 2.5 parts by weight of magnesium oxide as a dispersant were added and stirred to disperse. HFC-1 as a foaming agent
34a (CH 2 FCF 3) (boiling point -26.1 ° C., SP value 8.7
D) After press-fitting 40 parts by weight, the temperature was raised to 95 ° C and 48
Time impregnation was performed. Then, the mixture was cooled to 30 ° C. and taken out to obtain foaming agent-containing AS resin particles.
【００４５】この樹脂粒子を１０℃の保冷庫で保管し、
熟成した後スチームによって２５倍の発泡粒子を得た。
その発泡粒子を２０℃恒温室で保管した後、０．４ｋｇ
／ｃｍ2 のスチームで成形し成形品を得た。The resin particles are stored in a cool box at 10 ° C.,
After aging, 25 times more expanded particles were obtained by steam.
0.4 kg after storing the foamed particles in a thermostatic chamber at 20 ° C
A molded product was obtained by molding with steam of / cm 2 .
【００４６】この成形品も外観・融着ともに良好であっ
た。実施例１と同様、発泡剤量と熱伝導率を測定した結
果、表８のように発泡剤量・熱伝導率とも非常に変化の
小さい物であった。The appearance and fusion of this molded product were also good. As in Example 1, the amount of foaming agent and the thermal conductivity were measured. As a result, as shown in Table 8, both the amount of foaming agent and the thermal conductivity were very small.
【００４７】[0047]
【表８】 [Table 8]
【００４８】[0048]
【比較例１】ＡＮ含有量２４ｗｔ％のＡＳ樹脂１００重
量部を５リットルオートクレーブに入れ、これに水３０
０重量部と分散剤として酸化マグネシウム３重量部とを
加えて撹拌し分散させた。発泡剤としてＨＦＣ−１４２
ｂ(CH3CClF2)４０重量部を圧入したのち、１２０℃まで
昇温し２４時間含浸を行った。その後、３０℃まで冷却
し取り出して発泡剤含有ＡＳ樹脂粒子を得た。Comparative Example 1 100 parts by weight of AS resin having an AN content of 24 wt% was placed in a 5 liter autoclave, and water 30
0 part by weight and 3 parts by weight of magnesium oxide as a dispersant were added and stirred to disperse. HFC-142 as a foaming agent
After 40 parts by weight of b (CH 3 CClF 2 ) was pressed in, the temperature was raised to 120 ° C. and impregnation was carried out for 24 hours. Then, the mixture was cooled to 30 ° C. and taken out to obtain foaming agent-containing AS resin particles.
【００４９】この樹脂粒子を１０℃の保冷庫で保管し、
熟成した後スチームによって３０倍の発泡粒子を得た。
その発泡粒子を２０℃恒温室で保管した後、０．８ｋｇ
／ｃｍ2 のスチームで成形し成形品を得た。The resin particles are stored in a cool box at 10 ° C,
After aging, steam was used to obtain 30 times as many expanded particles.
0.8kg after storing the foamed particles in a constant temperature room at 20 ° C
A molded product was obtained by molding with steam of / cm 2 .
【００５０】成形品は外観・融着ともに良好であった。
この成形品中の発泡剤量と成形品の熱伝導率を経時をお
って測定した結果、表９のように発泡剤量・熱伝導率と
も非常に変化の大きい物であった。The molded product had good appearance and fusion.
As a result of measuring the amount of the foaming agent in this molded product and the thermal conductivity of the molded product over time, as shown in Table 9, both the amount of the foaming agent and the thermal conductivity were very large.
【００５１】[0051]
【表９】 [Table 9]
Claims (2)
量％のアクリロニトリル・スチレン共重合体で、メルト
フローレートが０．１〜２０ｇ／１０分、重量平均分子
量が２５，０００以上のＡＳ樹脂に、沸点が−５０〜＋
４０℃、溶解度パラメーターが８．０〜１１．０（ｃａ
ｌ／ｃｍ3 ）1/2 のハロゲン化脂肪族炭化水素を含ませ
てなるＡＳ樹脂製発泡性粒子。1. An AS resin having an acrylonitrile content of 25 to 50% by weight, an acrylonitrile-styrene copolymer having a melt flow rate of 0.1 to 20 g / 10 minutes and a weight average molecular weight of 25,000 or more, and a boiling point. Is -50 to +
40 degreeC, solubility parameter is 8.0-11.0 (ca
AS resin expandable particles containing 1 / cm 3 ) 1/2 of halogenated aliphatic hydrocarbon.
量％のアクリロニトリル・スチレン共重合体で、メルト
フローレートが０．１〜２０ｇ／１０分、重量平均分子
量が２５，０００以上のＡＳ樹脂に、沸点が−５０〜＋
４０℃、溶解度パラメーターが８．０〜１１．０（ｃａ
ｌ／ｃｍ3 ）1/2 のハロゲン化脂肪族炭化水素を含ませ
てなるＡＳ樹脂製発泡性粒子を加熱して発泡させるとと
もに互いに融着させ、発泡倍率を１０〜５０倍の成形体
としたことを特徴とするＡＳ樹脂製断熱材。2. An acrylonitrile / styrene copolymer having an acrylonitrile content of 25 to 50% by weight, a melt flow rate of 0.1 to 20 g / 10 min, an AS resin having a weight average molecular weight of 25,000 or more, and a boiling point. Is -50 to +
40 degreeC, solubility parameter is 8.0-11.0 (ca
1 / cm 3 ) 1/2 AS resin expandable particles containing a halogenated aliphatic hydrocarbon are heated to be foamed and fused to each other to obtain a molded product having an expansion ratio of 10 to 50 times. An AS resin heat insulating material characterized by the above.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22571194A JPH0859877A (en) | 1994-08-25 | 1994-08-25 | Expandable as resin particle and heat-insulation material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22571194A JPH0859877A (en) | 1994-08-25 | 1994-08-25 | Expandable as resin particle and heat-insulation material |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0859877A true JPH0859877A (en) | 1996-03-05 |
Family
ID=16833613
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22571194A Pending JPH0859877A (en) | 1994-08-25 | 1994-08-25 | Expandable as resin particle and heat-insulation material |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0859877A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2008130749A3 (en) * | 2007-04-16 | 2009-03-12 | Dow Global Technologies Inc | Alkenyl aromatic foam with low solubility hydrofluorocarbon |
| JP2009138373A (en) * | 2007-12-04 | 2009-06-25 | Kaneka Corp | Heat-insulating and waterproof structure and heat-insulating and waterproof construction method |
| JP2012214751A (en) * | 2011-03-30 | 2012-11-08 | Sekisui Plastics Co Ltd | Foamable polystyrene-based resin particle and production method therefor, polystyrene-based resin pre-foamed particle, and polystyrene-based resin foamed molding |
-
1994
- 1994-08-25 JP JP22571194A patent/JPH0859877A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2008130749A3 (en) * | 2007-04-16 | 2009-03-12 | Dow Global Technologies Inc | Alkenyl aromatic foam with low solubility hydrofluorocarbon |
| US8785510B2 (en) | 2007-04-16 | 2014-07-22 | Dow Global Technologies Llc | Alkenyl aromatic foam with low solubility hydrofluorocarbon |
| JP2009138373A (en) * | 2007-12-04 | 2009-06-25 | Kaneka Corp | Heat-insulating and waterproof structure and heat-insulating and waterproof construction method |
| JP2012214751A (en) * | 2011-03-30 | 2012-11-08 | Sekisui Plastics Co Ltd | Foamable polystyrene-based resin particle and production method therefor, polystyrene-based resin pre-foamed particle, and polystyrene-based resin foamed molding |
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