JP3903593B2 - Rigid polyurethane foam - Google Patents

Description

【００１６】
【化４】

【００１７】
本発明の硬質ポリウレタンフォームは、発泡剤として炭酸ガスを用いるため、オゾン層を破壊することがなく、かつ、地球温暖化の問題にも配慮したものである。
【００１８】
【発明の実施の形態】
以下に本発明の実施の形態を詳細に説明する。
【００１９】
本発明において用いるポリオール成分は、ヒドロキシ化合物と、ｏ−フタル酸、ｍ−フタル酸 ｐ−フタル酸及びこれらの誘導体よりなる群から選ばれる１種又は２種以上の多塩基酸成分とをエステル化反応させて得られるフタル酸系ポリエステルポリオールを４０重量％以上含む。ポリオール成分として、このように芳香環を含むフタル酸系ポリエステルポリオールを多く用いることにより、安定な難燃性を得ることができる。ポリオール成分中のフタル酸系ポリエステルポリオール含有量が４０重量％未満では十分な難燃性を得ることはできない。ポリオール成分中のフタル酸系ポリエステルポリオール含有量は好ましくは５０重量％以上、より好ましくは６０重量％以上であり、特に、フタル酸系ポリエステルポリオールを６０重量％以上用いることにより、安定的に難燃効果を得ることができる。
【００２０】
このフタル酸系ポリエステルポリオールを形成するヒドロキシ化合物としては、エチレングリコール、ジエチレングリコール等が挙げられ、フタル酸誘導体としてはフタル酸ジエチル、フタル酸ジメチル等が挙げられ、フタル酸系ポリエステルポリオールの好ましい水酸基価は１５０〜４５０である。フタル酸系ポリエステルポリオールは、特に、多塩基酸中のｍ−フタル酸及び／又はｐ−フタル酸の割合の高いものが難燃性の面からは好ましい。
【００２１】
なお、本発明に係るフタル酸系ポリエステルポリオールの含有量とは、純粋なフタル酸系ポリエステルポリオールとしての割合であり、エステル合成反応の生成物中に未反応の状態で含まれるヒドロキシ化合物や多塩基酸成分、その他の添加剤等は含まれない。
【００２２】
本発明においては、ポリオール成分として、上記フタル酸系ポリエステルポリオールの他、フェノール及び／又はその誘導体をマンニッヒ変性して得られたポリエーテルポリオール（以下、「マンニッヒ変性ポリオール」と称す。）、即ち、フェノール、或いはノニルフェノール、アルキルフェノール等のフェノール誘導体をホルムアルデヒドとジエタノールアミン等の２級アミンやアンモニア、１級アミン等を用いてマンニッヒ変性し、エチレンオキサイド、プロピレンオキサイド等のアルキレンオキサイドを開環付加重合して得られるポエーテルポリオールを用いても良い。このようなマンニッヒ変性ポリオールは、自己反応活性が高く、かつ難燃性も比較的高いため、マンニッヒ変性ポリオールを用いることにより、例えば、エアレススプレー発泡型硬質ポリウレタンフォームにあっては、吹き付け発泡時に難燃性能を著しく損なうことなく、速やかに反応を進めることができる。ただし、ポリオール成分中のマンニッヒ変性ポリオールが２０重量％を超えると難燃性能が悪化してくるため、マンニッヒ変性ポリオールを使用する場合、そのポリオール成分中の割合は２０重量％以下、特に５〜１５重量％とするのが好ましい。
【００２３】
本発明においては、ポリオール成分として、フタル酸系ポリエステルポリオール及びマンニッヒ変性ポリオールの他、本発明の目的を損なわない範囲で更にエチレンジアミン、トリレンジアミン、シュークロース、アミノアルコール、ジエチレングリコール等のマンニッヒ変性ポリオールとは異なる開始剤のポリオール化合物をポリオール成分中３０重量％以下の範囲で併用しても良い。
【００２４】
一方、ポリイソシアネート成分としては、前記一般式（Ｉ）で表されるポリイソシアネート化合物であって、このポリイソシアネート化合物中、ｎ≧３のポリメリックイソシアネートの割合（ポリイソシアネート中の５核体以上含有量）が３０モル％未満であり、かつ、ポリイソシアネート化合物中、前記構造式（II）で表される４，４’−ＭＤＩの割合（ＭＤＩ中の４，４’体含有量）が３６モル％以上の核体制御ポリイソシアネートを用いる。
【００２５】
この核体制御ポリイソシアネートのポリイソシアネート中の５核体以上含有量が３０モル％以上である場合、或いは、ポリイソシアネート中の４，４’体含有量が３６モル％未満である場合は、良好な難燃性を達成することはできない。
【００２６】
本発明に係る核体制御ポリイソシアネート中の５核体以上含有量は好ましくは５〜２５モル％であり、これが５モル％未満のものは合成プロセスが複雑で現状では工業生産が難しい。また、ポリイソシアネート中の４，４’体含有量は好ましくは３７モル％以上、より好ましくは３８モル％以上である。
【００２７】
なお、核体制御ポリイソシアネート中の２核体ジイソシアネートの割合は３５〜５０モル％、３核体トリイソシアネートの割合は２５〜５０モル％で、イソシアネート指数は１３０〜３５０であることが好ましく、難燃性の向上や収縮率の抑制等の全体の性能バランスを考慮した場合１５０〜２５０であることがより好ましい。
【００２８】
本発明においては、ポリイソシアネート成分として、上記核体制御ポリイソシアネート以外のポリイソシアネート化合物、例えば、イソホロンジイソシアネート等の脂環族系イソシアネート類、ヘキサメチレンジイソシアネート等の脂肪族系イソシアネート類等を用いても良いが、この場合においても全ポリイソシアネート成分中の前記５核体以上含有量及び４，４’体含有量が本発明の範囲内であることが必要となる。
【００２９】
本発明で用いる反応型アミン触媒は、１分子中に水酸基を１個以上含有するアミン化合物であり、具体的にはジメチルアミノヘキサノール、ジメチルアミノエトキシエタノール、トリメチルアミノエチルエタノールアミン、その他４級アンモニウム塩類等が挙げられる。
【００３０】
即ち、従来、硬質ポリウレタンフォームの触媒として用いられてきたアミン触媒は、トリエチレンジアミン、テトラメチルヘキサメチレンジアミン、ペンタメチルジエチレントリアミン等の化合物であるが、これらは官能基をもたず発泡体中にフリーの状態で残留するため、これが燃焼の核となっていたものと推定される。従って、本発明ではこうした従来のアミン触媒に代えて反応型アミン触媒を用いることにより難燃性を高める。
【００３１】
なお、ジブチル錫ジラウレート、オクチル酸鉛、スタナスオクトエート、オクチル酸カリウム（２−エチルヘキシル酸カリウム）、酢酸カリウムなどの有機金属系触媒は、ウレタン結合やイソシアヌレート変性促進において必須の成分であり、また、使用により難燃性を損なうものではないので、その使用は何ら差し支えない。
【００３２】
本発明において、上記反応型アミン触媒の使用量は、発泡条件、例えば、エアレススプレー発泡型硬質ポリウレタンフォームの場合には主に吹き付け環境温度条件によっても異なるが、ポリオール成分に対して１０重量％以下、好ましくは５重量％以下、より好ましくは０．１〜５重量％である。反応型アミン触媒の使用量がポリオール成分に対して１０重量％を超えると難燃性能がかえって低下する上に、エアレススプレー発泡型硬質ポリウレタンフォームの場合、スプレーパタン（霧化幅）が乱れ、好ましくない。
【００３３】
また、上記有機金属系触媒の使用量（反応型アミン触媒を用いる場合は反応型アミン触媒との合計量）は、ポリオール成分に対して１〜１０重量％とするのが好ましい。
【００３４】
本発明においては、発泡剤として炭酸ガスを用いる。発泡剤としての炭酸ガスは、水を添加して水とイソシアネートとの反応で生成させる方法により、或いは、原料成分中に液化炭酸ガスを強制混入する方法により、反応系内に添加することができる。
【００３５】
炭酸ガスの使用量は、目的とする硬質ポリウレタンフォームの密度によって任意に決定されるが、通常の場合、ポリオール成分とポリイソシアネート成分との合計に対して１２重量％以下、特に２．５〜８重量％とするのが好ましい。特に発泡剤として水をイソシアネートに反応させて炭酸ガスを発生させる場合、水の添加量はポリオール成分とポリイソシアネート成分との合計に対して１〜３重量％とするのが好ましい。炭酸ガスの使用量がポリオール成分とポリイソシアネート成分との合計に対して１２重量％を超えると、気化力が高くなりすぎて、発泡が不安定となり、気泡も粗大で良好なフォームが得られなくなる。
【００３６】
整泡剤としては、硬質ポリウレタンフォーム製造用として効果のあるものは全て使用できる。例えばポリオキシアルキレンアルキルエーテル等のシリコーン系のもの等を通常の使用量で用いることができる。
【００３７】
また、本発明においては、上記以外の任意の成分、例えば難燃剤、充填剤等も本発明の目的を妨げない範囲で使用することができる。
【００３８】
本発明の硬質ポリウレタンフォームは、発泡剤の炭酸ガスと、前記フタル酸系ポリエステルポリオールと反応型アミン触媒とを併用することを必須とするが、更にマンニッヒ変性ポリオール及び低沸点発泡剤を併用することで、より一層良好な特性を得ることができる。
【００３９】
本発明の硬質ポリウレタンフォームは、例えばエアレススプレー発泡型硬質ポリウレタンフォームの場合、発泡剤、触媒、整泡剤及びその他の助剤をポリオール成分に混合した配合成分と、ポリイソシアネート成分とを常法に従って３０〜５０℃でミキシングヘッドで混合し、施工対象面に吐出圧力４０〜８０Ｋｇ／ｃｍ^２で吹き付けて発泡させることにより容易に製造することができる。
【００４０】
また、注入成型による断熱パネルの場合は、発泡剤、触媒、整泡剤及びその他の助剤をポリオール成分に混合した配合成分と、ポリイソシアネート成分とを常法に従って１５〜５０℃でミキシングヘッドで混合、発泡して得られるイソシアヌレート変性硬質ポリウレタンフォーム原料を、表面材と側枠材とで構成される中空パネル本体の空洞部に注入し、発泡させて成型することにより容易に製造することができる。
【００４１】
この中空パネル本体の表面材としては、断熱パネルの使用目的により異なるが、アルミ、鉄、ステンレス、塩ビ鋼板等の金属ないし合金板、構造用合板、オリエンテッドストランドボード（ＯＳＢ）等の集成材等が挙げられる。
【００４２】
また、側枠材としては、塩ビやＡＢＳ等の樹脂成型品や木材等が一般に用いられる。
【００４３】
また、連続発泡成型による断熱ボードであれば、発泡剤、触媒、整泡剤及びその他の助剤をポリオール成分に混合した配合成分と、ポリイソシアネート成分とを常法に従って１５〜５０℃でミキシングヘッドで混合、発泡して得られるイソシアヌレート変性硬質ポリウレタンフォームに、表面材をラミネートし、ベルトコンベア等により圧締させる連続発泡成型法等により容易に製造することができる。
【００４４】
この場合の表面材としても、断熱ボードの使用目的により異なるが、アルミ箔、クラフト紙、アスファルトフェルトなどの軟質面材や、石膏ボード、木毛セメント板、合板などの硬質面材等が挙げられる。
【００４５】
このような断熱ボードは、その寸法に特に制約を受けるものではないが、一般的には、３０〜２００ｃｍ×１５０〜８００ｃｍ×厚さ１〜２０ｃｍ程度とされる。
【００４６】
【実施例】
以下に実施例及び比較例を挙げて本発明をより具体的に説明する。なお、以下において「％」は特記しない限り「重量％」を示す。
【００４７】
実施例１〜３，比較例１〜３
表１に示した配合処方に従って、まず配合液Ａを調製し、ポリイソシアネート１，２を用意した。
【００４８】
なお、用いた原料は次の通りである。
ポリオールＡ： 第一工業製薬（株）製
マンニッヒ変性ポリオール、水酸基価７００
ポリオールＢ： 第一工業製薬（株）製
マンニッヒ変性ポリオール、水酸基価４７０
ポリオールＣ： ヘキストセラニーズ（株）製
ｍ，ｐ−フタル酸ベースポリエステルポリオール、
水酸基価２４０
（ヒドロキシ化合物残存率１１％）
ポリオールＤ： 東邦理化工業（株）製
ｍ，ｐ−フタル酸ベースポリエステルポリオール、
水酸基価３００
（ヒドロキシ化合物残存率１５％）
ポリオールＥ： 東邦理化工業（株）製
ｏ−フタル酸ベースポリエステルポリオール、
水酸基価３００
（ヒドロキシ化合物残存率１５％）
ポリオールＦ： 東邦理化工業（株）製
ｏ−フタル酸ベースポリエステルポリオール、
水酸基価２６０
（ヒドロキシ化合物残存率１１％）
難燃剤： ストファージャパン（株）製「ファイロールＰＣＦ」
整泡剤： 日本ユニカー（株）製「Ｌ５４２０」
触媒Ａ： 花王（株）製「カオライザーＮｏ．１」
テトラメチルヘキサメチレンジアミン
触媒Ｂ： 花王（株）製「カオライザーＮｏ．２５」
反応型アミン触媒ジメチルアミノヘキサノール（１分子中の水酸
基数１）
触媒Ｃ： 花王（株）製「カオライザーＮｏ．３」
ペンタメチルジエチレントリアミン
触媒Ｄ： 日本化学産業（株）製「Ｂ−１５Ｇ」
２−エチルヘキシル酸カリウム
発泡剤：水
ポリイソシアネート１： 日本ポリウレタン（株）製
粗製ジフェニルメタンジイソシアネート
（ＮＣＯ ％：３０．２、ポリイソシアネート中
の５核体以上の含有量：２４モル％、ＭＤＩ含有
量：３７モル％、ＭＤＩ中の４，４’体含有量：
９９モル％）
ポリイソシアネート２： 住友バイエルウレタン（株）製
粗製ジフェニルメタンジイソシアネート
（ＮＣＯ ％：３１．４、ポリイソシアネート中
の５核体以上の含有量：２４モル％、ＭＤＩ含有
量：４６モル％、ＭＤＩ中の４，４’体含有量：
７７モル％）
配合液Ａと所定量のイソシアネート１又は２をいずれも２０℃に調整し、ラボミキサーにより５０００ｒｐｍで５秒間攪拌し雛型紙上にフリー発泡した。得られたフォームのコア部分を切出して、東洋精機製作所製燃焼性試験機により表面試験を実施し（試験体厚み２０ｍｍ、加熱時間１０分）、結果を表１に示した。
【００４９】
【表１】

【００５０】
表１より、発泡剤として炭酸ガスを用いると共に、フタル酸系ポリエステルポリオールと反応型アミン触媒を用いた本発明の硬質ポリウレタンフォームは、難燃性に優れることがわかる。
【００５１】
なお、上記実施例は、本発明をエアレススプレー発泡型硬質ポリウレタンフォームに適用したものであるが、本発明はエアレススプレー発泡型硬質ポリウレタンフォームに限らず、その他、注入成型による断熱パネル、連続発泡成型によるラミネートボード等にも有効に用いることができる。
【００５２】
【発明の効果】
以上詳述した通り、本発明の硬質ポリウレタンフォームによれば、発泡剤として炭酸ガスを用いて、難燃性に優れた硬質ポリウレタンフォームが提供される。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a rigid polyurethane foam, and more particularly to a rigid polyurethane foam obtained by foaming a polyisocyanate component and a blended liquid in which a polyol component, a foaming agent, a catalyst, a foam stabilizer and other auxiliary agents are mixed.
[0002]
[Prior art]
Rigid polyurethane foam is widely used as a heat insulating material for houses, refrigerators and the like because it is excellent in heat insulation and self-adhesion.
[0003]
Rigid polyurethane foams used in these applications are generally airless sprays in which a polyisocyanate component is mixed with a blended liquid in which a polyol component, a foaming agent, a catalyst, a foam stabilizer and other auxiliaries are mixed, and foamed by a mixing head. If it is obtained by foaming and this method is used, it is possible to form a heat insulating layer of a good rigid polyurethane foam by a simple operation of directly spraying the construction object.
[0004]
On the other hand, as a panel material used for heat insulation and partitioning in refrigerated / freezer warehouses and clean rooms, a heat insulation panel using a metal plate or structural plywood as a face material and sandwiching rigid polyurethane foam with high heat insulation performance was developed and put into practical use. ing.
[0005]
In general, such a thermal insulation panel using a rigid polyurethane foam as a thermal insulation material is obtained by mixing and foaming a polyisocyanate component and a compounded liquid in which a polyol component, a foaming agent, a catalyst, a foam stabilizer and other auxiliary agents are mixed. The isocyanurate-modified rigid polyurethane foam raw material obtained is manufactured by an injection molding method in which a raw material is injected into a hollow portion of a hollow panel body having a hollow portion composed of a surface material and a side frame material and integrally molded. The injection molding method can be arbitrarily designed with product dimensions, and can be molded integrally with the surface material and has high productivity, so it is widely adopted as a typical method for manufacturing heat insulation panels using rigid polyurethane foam. Has been.
[0006]
Also, for example, as a plate-like material used for heat insulation in commercial warehouses, etc., laminated board material laminated with non-combustible paper or gypsum face material on hard urethane foam, metal-type decorative face material or ceramic-type face material were laminated There is a siding material, and such a heat insulating board is generally obtained by mixing and foaming a polyisocyanate component and a blended liquid in which a polyol component, a foaming agent, a catalyst, a foam stabilizer and other auxiliary agents are mixed. It is manufactured by a continuous foaming method in which paper, veneer board, metal plate, gypsum board or the like is laminated and molded on isocyanurate-modified rigid polyurethane foam raw material, and then cut into a predetermined size. As a molding method by this continuous foaming, a double conveyor system in which a rigid polyurethane foam raw material is discharged from a mixing head onto a face material sent out by a pair of upper and lower belt conveyors, and pressed and molded in a foaming process, is representative. According to this method, the product dimensions can be arbitrarily designed, and it is widely adopted because it can be integrally formed with the surface material in one process and has high productivity.
[0007]
[Problems to be solved by the invention]
In rigid polyurethane foam, dichloromonofluoroethane (HCFC-141b), which is currently used as the main blowing agent, has a problem of ozone layer destruction. Hydrofluorocarbons (HFCs) that do not destroy the ozone layer are listed as candidates for next-generation foaming agents that can replace them, but on the other hand, they have a problem of strong global warming action. For this reason, development of a technique for foaming without using these fluorine-based foaming agents is considered as one issue.
[0008]
Therefore, in a rigid polyurethane foam by airless spray foaming, characteristics excellent in spraying stability, workability and flame retardancy are required without using these alternative foaming agents.
[0009]
On the other hand, rigid polyurethane foam as a thermal insulation material for thermal insulation panels used in homes and other applications has high flame resistance and can spread during a fire in addition to maintaining stable thermal insulation and airtightness for a long period of time. It is required to be difficult.
[0010]
That is, not only those using plywood as a surface material, but also those using a metal face material, depending on the material and thickness of the surface material, the panel structure, etc., sufficient fire resistance cannot be obtained, in the event of a fire There is a risk of igniting the internal rigid polyurethane foam in a short time. Therefore, the flame retardancy of rigid polyurethane foam is extremely important for use as a heat insulating panel.
[0011]
The present invention has been made in view of the above-described conventional situation, and an object thereof is to provide a rigid polyurethane foam that does not use HCFC-141b or HFC as a foaming agent and has excellent flame retardancy. To do.
[0012]
[Means for Solving the Problems]
The rigid polyurethane foam according to claim 1 is a rigid polyurethane foam obtained by mixing and foaming a polyisocyanate component, a polyol component, a foaming agent, a catalyst, a foam stabilizer and other auxiliary agents, and using carbon dioxide as the foaming agent. The polyol component is one or two or more polybasic compounds selected from the group consisting of hydroxy compounds, o-phthalic acid, m-phthalic acid, p-phthalic acid and derivatives thereof. Reaction comprising an amine compound containing 40% by weight or more of a polyester polyol compound (hereinafter referred to as “phthalic acid-based polyester polyol”) obtained by an esterification reaction with an acid component, and having one or more hydroxyl groups per molecule. The type amine catalyst is used in an amount of 10% by weight or less based on the polyol component.
[0013]
With this rigid polyurethane foam, extremely good flame retardancy can be obtained by using carbon dioxide as a foaming agent and using the phthalic polyester polyol and the reactive amine catalyst in combination.
[0014]
The rigid polyurethane foam according to claim 2 is a polyisocyanate compound represented by the following general formula (I) as the polyisocyanate component in the rigid polyurethane foam according to claim 1, wherein n ≧ 3 in the polyisocyanate compound. The proportion of the polymeric isocyanate is less than 30 mol% (hereinafter, this proportion is referred to as “content of five or more nuclei in the polyisocyanate”), and in the polyisocyanate compound, the following structural formula (II) The ratio of 4,4′-diphenylmethane diisocyanate (hereinafter referred to as “4,4′-MDI”) represented by the formula (hereinafter referred to as “4,4′-form content in polyisocyanate”). There is 36 mol% or more (hereinafter referred such polyisocyanates "karyoplast control polyisocyanate".) also used as In it, it is possible to obtain the phthalic acid based polyester polyol, a significantly better flame retardancy in combination with the reactive amine catalysts and the karyoplast control polyisocyanates.
[0015]
[Chemical 3]

[0016]
[Formula 4]

[0017]
Since the rigid polyurethane foam of the present invention uses carbon dioxide as a foaming agent, it does not destroy the ozone layer and also takes into consideration the problem of global warming.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail.
[0019]
The polyol component used in the present invention is an esterification of a hydroxy compound and one or more polybasic acid components selected from the group consisting of o-phthalic acid, m-phthalic acid, p-phthalic acid, and derivatives thereof. 40% by weight or more of phthalic polyester polyol obtained by reaction is included. By using a large amount of the phthalic polyester polyol containing an aromatic ring as described above, stable flame retardancy can be obtained. When the phthalic polyester polyol content in the polyol component is less than 40% by weight, sufficient flame retardancy cannot be obtained. The content of the phthalic polyester polyol in the polyol component is preferably 50% by weight or more, more preferably 60% by weight or more. In particular, by using 60% by weight or more of the phthalic polyester polyol, the flame retardant is stably flame retardant. An effect can be obtained.
[0020]
Examples of the hydroxy compound forming the phthalic polyester polyol include ethylene glycol and diethylene glycol. Examples of the phthalic acid derivative include diethyl phthalate and dimethyl phthalate. Preferred hydroxyl values of the phthalic polyester polyol are 150-450. As the phthalic acid-based polyester polyol, those having a high ratio of m-phthalic acid and / or p-phthalic acid in the polybasic acid are particularly preferable from the viewpoint of flame retardancy.
[0021]
The content of the phthalic polyester polyol according to the present invention is a ratio as a pure phthalic polyester polyol, and is a hydroxy compound or polybasic contained in an unreacted state in the product of the ester synthesis reaction. It does not contain acid components and other additives.
[0022]
In the present invention, as the polyol component, in addition to the above phthalic polyester polyol, polyether polyol obtained by modifying Mannich with phenol and / or its derivative (hereinafter referred to as “Mannich modified polyol”), that is, Phenol or phenol derivatives such as nonylphenol and alkylphenol are modified by Mannich modification with secondary amines such as formaldehyde and diethanolamine, ammonia and primary amines, and obtained by ring-opening addition polymerization of alkylene oxides such as ethylene oxide and propylene oxide. A polyether polyol may be used. Such a Mannich-modified polyol has a high self-reactive activity and a relatively high flame retardancy. Therefore, by using a Mannich-modified polyol, for example, in the case of an airless spray foam type rigid polyurethane foam, it is difficult to spray and foam. The reaction can proceed promptly without significantly impairing the fuel performance. However, when the Mannich modified polyol in the polyol component exceeds 20% by weight, the flame retardancy is deteriorated. Therefore, when the Mannich modified polyol is used, the proportion in the polyol component is 20% by weight or less, particularly 5 to 15%. It is preferable to set it as weight%.
[0023]
In the present invention, as the polyol component, in addition to the phthalic polyester polyol and Mannich modified polyol, Mannich modified polyols such as ethylenediamine, tolylenediamine, sucrose, amino alcohol, diethylene glycol and the like may be used as long as the object of the present invention is not impaired. The polyol compounds of different initiators may be used in combination within a range of 30% by weight or less in the polyol component.
[0024]
On the other hand, the polyisocyanate component is a polyisocyanate compound represented by the above general formula (I), and the ratio of n ≧ 3 polymeric isocyanate in the polyisocyanate compound (content of five or more nuclei in the polyisocyanate) ) Is less than 30 mol%, and the proportion of 4,4′-MDI represented by the structural formula (II) in the polyisocyanate compound (content of 4,4 ′ form in MDI) is 36 mol%. The above nucleus-controlling polyisocyanate is used.
[0025]
Good when the content of 5 nuclei or more in the polyisocyanate of this nuclei control polyisocyanate is 30 mol% or more, or when the content of 4,4 ′ isomer in the polyisocyanate is less than 36 mol% Flame retardant cannot be achieved.
[0026]
The content of five or more nuclei in the nucleus-controlled polyisocyanate according to the present invention is preferably 5 to 25 mol%, and if it is less than 5 mol%, the synthesis process is complicated and industrial production is difficult at present. Further, the 4,4′-form content in the polyisocyanate is preferably 37 mol% or more, more preferably 38 mol% or more.
[0027]
The ratio of the dinuclear diisocyanate in the nucleus control polyisocyanate is 35 to 50 mol%, the ratio of the trinuclear triisocyanate is 25 to 50 mol%, and the isocyanate index is preferably 130 to 350. In consideration of the overall performance balance such as improvement of flammability and suppression of shrinkage, it is more preferably 150 to 250.
[0028]
In the present invention, as the polyisocyanate component, polyisocyanate compounds other than the above-mentioned nucleus-controlling polyisocyanate, for example, alicyclic isocyanates such as isophorone diisocyanate, aliphatic isocyanates such as hexamethylene diisocyanate, and the like may be used. Even in this case, it is necessary that the content of the five or more nuclei and the content of the 4,4 ′ isomer in the total polyisocyanate component are within the scope of the present invention.
[0029]
The reactive amine catalyst used in the present invention is an amine compound containing one or more hydroxyl groups in one molecule, specifically, dimethylaminohexanol, dimethylaminoethoxyethanol, trimethylaminoethylethanolamine, and other quaternary ammonium salts. Etc.
[0030]
That is, amine catalysts that have been used as catalysts for rigid polyurethane foams are compounds such as triethylenediamine, tetramethylhexamethylenediamine, pentamethyldiethylenetriamine, etc., but these have no functional groups and are free in the foam. It is estimated that this was the core of combustion. Accordingly, in the present invention, flame retardancy is enhanced by using a reactive amine catalyst instead of such a conventional amine catalyst.
[0031]
In addition, organometallic catalysts such as dibutyltin dilaurate, lead octylate, stannous octoate, potassium octylate (potassium 2-ethylhexylate), and potassium acetate are essential components for promoting urethane bonds and isocyanurate modification, Moreover, since use does not impair flame retardance, the use does not interfere.
[0032]
In the present invention, the amount of the reactive amine catalyst used is 10% by weight or less based on the polyol component, although it varies depending on foaming conditions, for example, airless spray foam type rigid polyurethane foam, mainly depending on the spraying environmental temperature conditions. , Preferably 5% by weight or less, more preferably 0.1 to 5% by weight. When the amount of the reactive amine catalyst used exceeds 10% by weight with respect to the polyol component, the flame retardancy is reduced, and in the case of airless spray foamed rigid polyurethane foam, the spray pattern (atomization width) is disturbed. Absent.
[0033]
Moreover, it is preferable that the usage-amount (the total amount with a reactive amine catalyst, when using a reactive amine catalyst) of the said organometallic catalyst shall be 1-10 weight% with respect to a polyol component.
[0034]
In the present invention, carbon dioxide gas is used as the foaming agent. Carbon dioxide gas as a foaming agent can be added to the reaction system by a method in which water is added and produced by a reaction between water and isocyanate, or by a method in which liquefied carbon dioxide gas is forcibly mixed into the raw material components. .
[0035]
The amount of carbon dioxide used is arbitrarily determined depending on the density of the target rigid polyurethane foam, but is usually 12% by weight or less, particularly 2.5 to 8%, based on the total of the polyol component and the polyisocyanate component. It is preferable to set it as weight%. In particular, when water is reacted with isocyanate as a blowing agent to generate carbon dioxide, the amount of water added is preferably 1 to 3% by weight based on the total of the polyol component and the polyisocyanate component. If the amount of carbon dioxide used exceeds 12% by weight based on the total of the polyol component and the polyisocyanate component, the vaporizing power becomes too high, foaming becomes unstable, and the foam is too coarse to obtain a good foam. .
[0036]
Any foam stabilizer that is effective for producing rigid polyurethane foam can be used. For example, a silicone-based material such as polyoxyalkylene alkyl ether can be used in a usual amount.
[0037]
Moreover, in this invention, arbitrary components other than the above, for example, a flame retardant, a filler, etc. can be used in the range which does not interfere with the objective of this invention.
[0038]
Rigid polyurethane foam of the present invention, a carbon dioxide blowing agent, although essential and that the combined use of catalyze reactive amine and the phthalic acid based polyester polyol, further a combination of Mannich-modified polyol and a low-boiling blowing agent As a result, even better characteristics can be obtained.
[0039]
When the rigid polyurethane foam of the present invention is, for example, an airless spray foam type rigid polyurethane foam, a blending component obtained by mixing a foaming agent, a catalyst, a foam stabilizer and other auxiliaries with a polyol component, and a polyisocyanate component according to a conventional method. It can manufacture easily by mixing with a mixing head at 30-50 degreeC, and spraying and foaming to a construction object surface with discharge pressure 40-80Kg / cm < ² >.
[0040]
In addition, in the case of a heat insulating panel by injection molding, a blending component obtained by mixing a foaming agent, a catalyst, a foam stabilizer and other auxiliary agents with a polyol component, and a polyisocyanate component are mixed at 15 to 50 ° C. according to a conventional method. Isocyanurate-modified rigid polyurethane foam raw material obtained by mixing and foaming can be easily manufactured by pouring into a hollow part of a hollow panel body composed of a surface material and a side frame material, foaming and molding it can.
[0041]
The surface material of the hollow panel body varies depending on the purpose of use of the heat insulating panel, but is made of metal or alloy plate such as aluminum, iron, stainless steel, PVC steel plate, laminated plywood for construction, or oriented strand board (OSB). Is mentioned.
[0042]
As the side frame material, resin molded products such as vinyl chloride and ABS, and wood are generally used.
[0043]
Moreover, if it is a heat insulation board by continuous foam molding, a mixing component obtained by mixing a foaming agent, a catalyst, a foam stabilizer and other auxiliaries with a polyol component, and a polyisocyanate component at 15 to 50 ° C. according to a conventional method. Can be easily manufactured by a continuous foam molding method or the like in which a surface material is laminated on an isocyanurate-modified rigid polyurethane foam obtained by mixing and foaming with a belt conveyor and pressed by a belt conveyor or the like.
[0044]
The surface material in this case also varies depending on the purpose of use of the heat insulating board, but includes soft surface materials such as aluminum foil, kraft paper, and asphalt felt, and hard surface materials such as gypsum board, wood cement board, and plywood. .
[0045]
Although such a heat insulation board does not receive a restriction | limiting in particular in the dimension, Generally, it is set as about 30-200cmx150-800cmx thickness 1-20cm.
[0046]
【Example】
Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples. In the following, “%” means “% by weight” unless otherwise specified.
[0047]
Examples 1 to 3 and Comparative Examples 1 to 3
According to the blending formulation shown in Table 1, first, a blending liquid A was prepared, and polyisocyanates 1 and 2 were prepared.
[0048]
In addition, the used raw material is as follows.
Polyol A: Daiichi Kogyo Seiyaku Co., Ltd.
Mannich modified polyol, hydroxyl value 700
Polyol B: manufactured by Daiichi Kogyo Seiyaku Co., Ltd.
Mannich modified polyol, hydroxyl value 470
Polyol C: manufactured by Hoechst Celanese
m, p-phthalic acid-based polyester polyol,
Hydroxyl value 240
(Hydroxy compound residual ratio 11%)
Polyol D: Toho Rika Kogyo Co., Ltd.
m, p-phthalic acid-based polyester polyol,
Hydroxyl value 300
(Hydroxy compound residual ratio 15%)
Polyol E: Toho Rika Kogyo Co., Ltd.
o-phthalic acid-based polyester polyol,
Hydroxyl value 300
(Hydroxy compound residual ratio 15%)
Polyol F: Toho Rika Kogyo Co., Ltd.
o-phthalic acid-based polyester polyol,
Hydroxyl value 260
(Hydroxy compound residual ratio 11%)
Flame retardant: “Firoll PCF” manufactured by Stoffer Japan Co., Ltd.
Foam stabilizer: Nippon Unicar Co., Ltd. “L5420”
Catalyst A: Kao Riser No. 1 manufactured by Kao Corporation
Tetramethylhexamethylenediamine Catalyst B: Kao Riser No. 25 manufactured by Kao Corporation
Reactive amine catalyst dimethylaminohexanol (hydroxy acid in one molecule
Radix 1)
Catalyst C: Kao Riser No. 3 manufactured by Kao Corporation
Pentamethyldiethylenetriamine Catalyst D: “B-15G” manufactured by Nippon Chemical Industry Co., Ltd.
Potassium 2-ethylhexylate Foaming agent: Water Polyisocyanate 1: Nippon Polyurethane Co., Ltd.
Crude diphenylmethane diisocyanate
(NCO%: 30.2, in polyisocyanate
Of 5 or more nuclei: 24 mol%, MDI included
Amount: 37 mol%, 4,4 ′ body content in MDI:
99 mol%)
Polyisocyanate 2: manufactured by Sumitomo Bayer Urethane Co., Ltd.
Crude diphenylmethane diisocyanate
(NCO%: 31.4, in polyisocyanate
Of 5 or more nuclei: 24 mol%, MDI included
Amount: 46 mol%, 4,4 ′ body content in MDI:
77 mol%)
The blended liquid A and a predetermined amount of isocyanate 1 or 2 were both adjusted to 20 ° C., stirred for 5 seconds at 5000 rpm with a laboratory mixer, and free-foamed on the template paper. The core part of the obtained foam was cut out and subjected to a surface test using a flammability tester manufactured by Toyo Seiki Seisakusho (test specimen thickness 20 mm, heating time 10 minutes). The results are shown in Table 1.
[0049]
[Table 1]

[0050]
From Table 1, the use of carbon dioxide as a blowing agent, a rigid polyurethane foam of the present invention using a reactive amine catalysts and phthalic acid based polyester polyols, it is understood that excellent flame retardancy.
[0051]
In addition, although the said Example applies this invention to an airless spray foam type rigid polyurethane foam, this invention is not limited to an airless spray foam type rigid polyurethane foam, In addition, the heat insulation panel by injection molding, continuous foam molding Can also be used effectively for laminate boards.
[0052]
【The invention's effect】
As described above in detail, according to the rigid polyurethane foam of the present invention, a rigid polyurethane foam excellent in flame retardancy is provided by using carbon dioxide as a foaming agent.

Claims (2)

In a rigid polyurethane foam obtained by mixing and foaming a polyisocyanate component, a polyol component, a foaming agent, a catalyst, a foam stabilizer and other auxiliary agents,
A rigid polyurethane foam using carbon dioxide gas as the foaming agent,
The polyol component is an esterification reaction between a hydroxy compound and one or more polybasic acid components selected from the group consisting of o-phthalic acid, m-phthalic acid, p-phthalic acid and derivatives thereof. Containing 40% by weight or more of a polyester polyol compound obtained by
A rigid polyurethane foam, wherein a reactive amine catalyst comprising an amine compound having one or more hydroxyl groups per molecule is used in an amount of 10% by weight or less based on the polyol component. The polyisocyanate component according to claim 1, wherein the polyisocyanate component is a polyisocyanate compound represented by the following general formula (I), and a ratio of n = 3 polymeric isocyanate is less than 30 mol% in the polyisocyanate compound, and A rigid polyurethane foam characterized in that the ratio of 4,4′-diphenylmethane diisocyanate represented by the following structural formula (II) in the polyisocyanate compound is 36 mol% or more.