Summary of the invention
The objective of the invention is provides a kind of wide aperture polymethacrylimide plastic foam and preparation method thereof in order to satisfy the requirement to the stripping strength of matrix material.
In order to achieve the above object, the invention discloses a kind of wide aperture polymethacrylimide plastic foam, be prepared from by the raw material of following weight proportion:
Methacrylic acid 40-60 part,
Vinyl cyanide 40-60 part,
The 3rd monomer 5-20 part,
Thickening material 1-30 part,
Initiator 0.05-0.6 part,
Whipping agent 1-18 part,
Linking agent 1-12 part,
Density-controlling agent 0.1-3 part,
Nucleator 0.3-18 part;
Wherein initiator comprises peroxide radical initiator and azo radical initiator, and preferably the peroxidation acid tert-butyl ester, Diisopropyl azodicarboxylate and t-butylperoxyl benzoate is composite, and three's optimum compound proportion example is 5:1:2.Whipping agent is one or more in urea, Virahol or the isopropylcarbinol, and preferably urea and Virahol is composite, and both optimum compound proportions example is 1:1.
Thickening material is gas phase SiO
2, in the organobentonite, diatomite, methylcellulose gum, gelatin one or more, preferred gas phase SiO
2Specific surface area is 50-250m
2/ g.And gas phase SiO
2Or the consumption of other thickening materials is the 1-30wt% of methacrylic acid and vinyl cyanide gross weight.
The 3rd monomer is acrylic amide or the alkyl-acrylates that contains two keys, such as in acrylamide, Methacrylamide, methyl acrylate, ethyl propenoate, the butyl acrylate one or more.
Linking agent is allyl acrylate, allyl methacrylate(AMA), magnesium oxide or Ethylene glycol dimethacrylate.
Nucleator is Tert-butyl Methacrylate, N-METHYLFORMAMIDE or Propenoic acid, 2-methyl, isobutyl ester.
The preferred maleimide of density-controlling agent.
The present invention also provides the preparation method of above-mentioned wide aperture polymethacrylimide plastic foam, and the method is take methacrylic acid, vinyl cyanide and the 3rd monomer as raw material, by adding gas phase SiO
2Or various thickening materials, add simultaneously initiator, whipping agent, linking agent, density-controlling agent and the direct copolymerization of nucleator single stage method and obtain the copolymerization plate of methacrylic acid/vinyl cyanide, make polymethacrylimide plastic foam through high temperature foaming and thermal treatment again, specifically may further comprise the steps:
(1) mixing solutions preparation: raw material methacrylic acid, vinyl cyanide, the 3rd monomer, thickening material are mixed, then add initiator, whipping agent, linking agent, density-controlling agent, nucleator and mix, for subsequent use;
(2) copolymerization plate preparation: the mixing solutions of step (1) preparation is injected in two parallel glass by the India-rubber strip good seal, 30 ℃-70 ℃ lower polyreaction 10-70 hour, form methacrylic acid/acrylonitrile compolymer plate;
(3) foaming: with the copolymerization plate of step (2) preparation at 80 ℃ of-180 ℃ of lower preheating 2-10 hours, then at 180 ℃-230 ℃ lower foaming 10min-200min;
(4) thermal treatment: with the copolymerization plate of step (3) after foaming under 100 ℃ of-200 ℃ of conditions thermal treatment 1-5 hour, namely obtain described wide aperture polymethacrylimide plastic foam.
The present invention is by the kind of change whipping agent and initiator, thus the pore size of the polymethacrylimide plastic foam that makes; Utilize multiple initiator composite, and two kinds of whipping agents of physics and chemistry are composite, form the small-bore by pneumatogen, at high temperature decompose further expansion foam aperture in conjunction with chemical foaming agent such as urea, can better control the pore size of formation, the PMI foam mean pore size that finally makes is about 1600 μ m.The foam aperture of the present invention's preparation is relatively large, can form relative firmly combination with covering, can be applicable to some for the demanding occasion of the stripping strength of matrix material.
Embodiment
Below in conjunction with specific embodiment wide aperture of the present invention Polymethacrylimide is elaborated.
Embodiment 1
The prescription of a kind of wide aperture polymethacrylimide plastic foam is as follows:
Methacrylic acid |
50 |
Vinyl cyanide |
50 |
Methacrylamide |
8 |
Gas phase SiO
2 |
10 |
The peroxidation acid tert-butyl ester |
0.25 |
Diisopropyl azodicarboxylate |
0.05 |
T-butylperoxyl benzoate |
0.1 |
Virahol |
8 |
Urea |
8 |
Allyl methacrylate(AMA) |
5 |
Maleimide |
2.2 |
Tert-butyl Methacrylate |
4 |
Preparation method's step is as follows:
(1) mixing solutions preparation: with methacrylic acid, vinyl cyanide, Methacrylamide and gas phase SiO
2Mix, then add the peroxidation acid tert-butyl ester, Diisopropyl azodicarboxylate, t-butylperoxyl benzoate, Virahol, urea, allyl methacrylate(AMA), maleimide and Tert-butyl Methacrylate and mix according to as above filling a prescription.
(2) copolymerization plate preparation: in the two piece parallel glass of step (1) gained mixing solutions injection by the India-rubber strip good seal, polyreaction formed methacrylic acid/acrylonitrile compolymer plate in 50 hours under 45 ℃ of bath temperature conditions.
(3) foaming: with preheating under 140-150 ℃ of condition of copolymerization plate placement 5 hours, 50min again foamed under 200 ℃ of conditions.
(4) thermal treatment: the thermal treatment 2 hours under 170 ℃ of conditions of the copolymerization plate after will foaming namely obtains polymethacrylimide plastic foam.
The mean pore size of the polymethacrylimide plastic foam that the present embodiment makes is 1600 μ m, is the PMI foam of macroporous type, can be applicable to the demanding occasion of effects on surface stripping strength.
Embodiment 2
The prescription of a kind of wide aperture polymethacrylimide plastic foam is as follows:
Methacrylic acid |
40 |
Vinyl cyanide |
40 |
Methyl acrylate |
5 |
Diatomite |
2 |
The peroxidation acid tert-butyl ester |
0.05 |
Diisopropyl azodicarboxylate |
0.05 |
Urea |
2 |
Magnesium oxide |
1 |
Maleimide |
0.2 |
Propenoic acid, 2-methyl, isobutyl ester |
0.4 |
Preparation method's step is as follows:
(1) mixing solutions preparation: methacrylic acid, vinyl cyanide, methyl acrylate and diatomite are mixed, then add the peroxidation acid tert-butyl ester, Diisopropyl azodicarboxylate, urea, magnesium oxide, maleimide and Propenoic acid, 2-methyl, isobutyl ester and mix according to as above filling a prescription.
(2) copolymerization plate preparation: in the two piece parallel glass of step (1) gained mixing solutions injection by the India-rubber strip good seal, polyreaction formed methacrylic acid/acrylonitrile compolymer plate in 10 hours under 30 ℃ of bath temperature conditions.
(3) foaming: with preheating under 80-90 ℃ of condition of copolymerization plate placement 8 hours, 10min again foamed under 180 ℃ of conditions.
(4) thermal treatment: the thermal treatment 5 hours under 100 ℃ of conditions of the copolymerization plate after will foaming namely obtains polymethacrylimide plastic foam.
The mean pore size of the polymethacrylimide plastic foam that the present embodiment makes is 1540 μ m, is the PMI foam of macroporous type, can be applicable to the demanding occasion of effects on surface stripping strength.
Embodiment 3
The prescription of a kind of wide aperture polymethacrylimide plastic foam is as follows:
Methacrylic acid |
60 |
Vinyl cyanide |
60 |
Acrylamide |
20 |
Gas phase SiO
2 |
30 |
The peroxidation acid tert-butyl ester |
0.35 |
Diisopropyl azodicarboxylate |
0.05 |
T-butylperoxyl benzoate |
0.2 |
Isopropylcarbinol |
9 |
Urea |
8 |
Allyl methacrylate(AMA) |
12 |
Maleimide |
3 |
Tert-butyl Methacrylate |
16 |
Preparation method's step is as follows:
(1) mixing solutions preparation: with methacrylic acid, vinyl cyanide, acrylamide and gas phase SiO
2Mix, then add the peroxidation acid tert-butyl ester, Diisopropyl azodicarboxylate, t-butylperoxyl benzoate, isopropylcarbinol, urea, allyl methacrylate(AMA), maleimide and Tert-butyl Methacrylate and mix according to as above filling a prescription.
(2) copolymerization plate preparation: in the two piece parallel glass of step (1) gained mixing solutions injection by the India-rubber strip good seal, polyreaction formed methacrylic acid/acrylonitrile compolymer plate in 10 hours under 70 ℃ of bath temperature conditions.
(3) foaming: with preheating under 170-180 ℃ of condition of copolymerization plate placement 2 hours, 10min again foamed under 230 ℃ of conditions.
(4) thermal treatment: the thermal treatment 1 hour under 200 ℃ of conditions of the copolymerization plate after will foaming namely obtains polymethacrylimide plastic foam.
The mean pore size of the polymethacrylimide plastic foam that the present embodiment makes is 1560 μ m, is the PMI foam of macroporous type, can be applicable to the demanding occasion of effects on surface stripping strength.
The comparative example 1
The preparation of a kind of conventional hole polymethacrylimide plastic foam, fill a prescription as follows:
Methacrylic acid |
50 |
Vinyl cyanide |
50 |
Methacrylamide |
8 |
Gas phase SiO
2 |
10 |
The peroxidation acid tert-butyl ester |
0.3 |
Diisopropyl azodicarboxylate |
0.05 |
Virahol |
10 |
Allyl methacrylate(AMA) |
5 |
Maleimide |
2.2 |
Tert-butyl Methacrylate |
4 |
Above-mentioned polymethacrylimide foam material preparation method step is as follows:
(1) with methacrylic acid, vinyl cyanide, Methacrylamide, gas phase SiO
2Mix, the adding peroxidation acid tert-butyl ester, Diisopropyl azodicarboxylate, Virahol, allyl methacrylate(AMA), maleimide, Tert-butyl Methacrylate mix according to as above filling a prescription.
(2) with in two parallel glass of step (1) gained solution injection by the India-rubber strip good seal, polyreaction formed methacrylic acid/acrylonitrile compolymer plate in 50 hours under 45 ℃ of bath temperature conditions.
(3) with preheating under 100-150 ℃ of condition of copolymerization plate placement 5 hours, the 50min that foams under 200 ℃ of conditions again obtained polymethacrylimide foam.
(4) with the thermal treatment 2 hours under 170 ℃ of conditions of the polymethacrylimide foam that makes, obtain polymethacrylimide foam material.
The mean pore size of the polymethacrylimide plastic foam that this comparative example makes is 500 μ m, is the PMI foam of conventional type, can be applicable to generally to less demanding application scenario, aperture.
Compare with the polymethacrylimide plastic foam of comparative example's 1 preparation, embodiment 1 to 3 is by the polymethacrylimide plastic foam of the inventive method preparation, the aperture is relatively large, can form relative firmly combination with covering, be applied to some for the demanding occasion of the stripping strength of matrix material.