DE1301083B - Process for the production of copolymers reinforced with glass fibers - Google Patents

Description

1 2

It is known that a polydiolefin wherein R is an unsaturated group, e.g. B. a vinyl, styrene and a relatively small amount of divinyl, allyl, methallyl or crotonyl group, η contains a positive benzene, by curing a useful layer integer from 1 to 3 and R ₁ can produce an alkyl or aryl material . One has also already come from a group or is a substitution product of the same. resinable mixture which, as a monomeric compound, reacts stronger groups in the glass. The unsaturated part of the plastics is made. Molecule, e.g. B. the vinyl group, which via the silicon

So far, styrene has been used and the ring substituted atom attached to the glass, reacts with the polytuated Alkylstyrenes as crosslinking agents for immense and thereby binds the polymer and the glass saturated Polyester and liquid hydrocarbon resins are solidly combined with one another. Verbinaus are used as binding agents Polydienes. α-Methylstyrene can be fertilized with these fertilizers in the manner of vinylsilane, preferably with resins do not use. Hence it was assumed that it turns, but one can also use a complex compound also aromatic polyalkyl compounds, which are not used, which are saturated by bringing together methacrylic compounds Containing isopropenyl groups, unsuitable acid has been made with chromium chloride. would be. This has proven to be correct in the case of polyesters. 15 Specific monomeric styrene compounds are proven. o-methylstyrene, m-methylstyrene, p-methylstyrene,

It has now been found that technically special o-ethylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, this valuable mixed poly- 2,3-dimethylstyrene, 2,5-dimethylstyrene, p-tert-butyl merisate reinforced with glass fibers obtained when glass fibers with a monostyrene, o-chlorostyrene, m-chlorostyrene, p-chlorostyrene, meren styrene compound of the general formula 20 2,4,6-trichlorostyrene, mono-, di- and trifluorostyrene,

1,4-diethylstyrene, l-methyl-4-chlorostyrene, m-bromostyrene, o-bromostyrene, p-bromostyrene, 2,4-dichlorostyrene, 2,5-dichlorostyrene, 2,6-dichlorostyrene, dibromo-

CH = CH ₂ styrenes and mixtures of these compounds. Of the

The proportion of the styrene compound is generally 99.5 to 70 parts per 100 parts of the total mixture. A smaller part of the monomeric styrene can be replaced by other monomers, e.g. B. acrylonitrile, diethyl fumarate or butyl methacrylate. 30 A monomeric, by two or more isopropenyl groups and

in which R, R ₁ , R ₂ , R ₃ and R _{4 are} hydrogen or halogen, optionally substituted by halogen or alkyl radicals or alkyl radicals with not more than 18 carbon atoms incorporated and these mean atoms of substance, and a monomeric, polymerized by monomer mixture , two or more isopropenyl groups and any given 35 The two isopropenyl groups must either be in the meta or para position if they are substituted by halogen atoms or alkyl radicals. Specific th benzene compound added and the monomer examples are diisopropenylbenzene, diisopropenyl mixture polymerized in a manner known per se. toluene, diisopropenylxylene or triisopropenylbenzene.

Glass fibers are used as reinforcing materials, preferably diisopropenylbenzene is used, z. B. endless yarns, fiberglass strands, reinforcement 40 with the amount in a large range, z. B. from mats, staple fibers, woven fabrics, chopped fibers, or 0.5 to 25 parts. The diisopropenylbenzene Glass flakes. The reinforcing agents can be added to the polymerizable mixture before 35 to 80 Percentage by weight of the reinforced plastic is exposed to be partially polymerized. This lets make, expediently 60 to 70 percent by weight. Which is the viscosity of the mixture on each desired fiberglass usually wear a protective cover. 45 Set the th value. With this procedure you give As protective coatings z. B. Mixtures of starch preferably 0.5 to 30 parts of the polymer and mineral oils, polyvinyl acetate, polyisobutylene, 100 parts of the monomeric mixture. In general Copolymers of isobutylene and isoprene and polymers with a molecular copolymers are used made of butadiene and styrene. Inventive weight of at least 2000, preferably of at least according to a glass fiber can also be used 50 at least 5000.

those with a surface agent (a coupling agent)

agent), usually added to an unsaturated SiIi mixture, usually in an amount of a cium or chromium compound. from 0.5 to 3 parts. Preferably used is Such a coating makes usually 0.2 to 0.5 ° / ₀ peroxides, hydroperoxides, peresters and peracids, the glass weight is made. An example of this is an unsaturated 55 benzoyl peroxide used in reactions that use saturated halosilane of the formula - at a relatively low temperature

should. On the other hand, a combination of benzoyl peroxide and dicumyl peroxide is preferably used when the polymerization takes place in a temperature

where R is a vinyl or alkyl group, η a positive ^{6o be} g? ^h 7 ^{on about} .. ^ ^{to 150} ° ^C 7 ° ^ ° ™ ™. ^r , ^d · integer from 1 to 3 and X is a halogen. Instead of the invention, 0 5 to 35 parts,

to coat the fiberglass, you can also use 0.1 to 1 ° ™ & ?? f, ^{2, bls} P / parts of a rubber with 5 parts of a vinyl or Allylsilanesters, the general ^{h. Ohem} mw _Ic ht, are introduced into the monomeric mixture my formula, z. B. natural rubber, synthetic

65 cal polyisomers, gutta-percha or butadiene poly-

R 'Si (OR _{1) 4} - _7l mers and -mischpolymeren. The purpose of adding rubber is to incorporate the viscosity of the Gehat into the polymerizable mixture, a mixture of styrene and diisopropenylbenzene

set the desired value. In addition, this gives the mixture further favorable properties awarded. Natural rubber is preferably used, e.g. B. the so-called light crepe or synthetic polyisoprenes with 1,4 structure. Polystyrene is also suitable for adjusting the viscosity by emulsion polymerization and a molecular weight of at least 1,000,000 Has. The types of rubber used as thickeners are those which are compatible with the monomeric Mixture react together and form clear, homogeneous casting compounds. Fillers, such as finely divided Silicas, types of glass, types of clay and types of carbon black can be incorporated into the mixture. Further you can also use an anti-aging agent, e.g. B. 2,6-di-tert-butyl-p-cresol, in an amount of 0.1 to Work 4 parts into the mixture.

The reinforcing fabric is formed into layers with the polymerizable mixture. The connection of the monomeric mixture to the reinforcing substance ao can be achieved by known methods. That Material can be brought into any desired shape by pre-setting or compression molding. The monomer mixture can e.g. B. be connected by brush impregnation with a glass fabric; one can You can also pour it in the middle of several piles of dry tissue or you can put the tissue into the Dip the resin mixture. To produce cylindrical hollow pipes or lines, glass fibers can be inserted into the Dip the monomer mixture and wrap it around a steel mandrel. For example, those are called fiberglass strands present fibers at a certain angle to the axis of the mandrel circular in superimposed Layers wrapped so that a shell is formed around the pipe. After the desired Once the shape is reached, the coil is heated and a uniform rigid tube is formed.

The reinforcing materials processed into layers with the monomeric mixture are subjected to polymerizing conditions in a manner known per se, e.g. B. by heating in a mold at a temperature between 50 and 150 ° C within 1 minute to 2 hours. If necessary, one can ^{post-heating at 95 to 205 0} C within 10 minutes to 2 hours.

According to one embodiment of the invention, said aromatic isopropenyl monomers, a peroxide catalyst and a styrene compound, e.g. B. vinyl toluene, incorporated into a polydiolefin mixture and this mixture is processed into layers with a reinforcing material and at higher temperatures subjected to polymerizing conditions in a manner similar to that described above.

The polydiolefins can be made from conjugated diolefins with 4 to 6 carbon atoms in the molecule, z. B. butadiene, hexadiene, isoprene, dimethylbutadiene, piperylene or methylpentadiene have been produced be. Copolymers of these diolefins with smaller amounts of ethylenically unsaturated monomers, ζ. Β. Styrene, acrylonitrile, methyl vinyl ketone or substituted with styrenes in the alkyl groups on the ring are e.g. B. p-methylstyrene and dimethylstyrene come in question. A preferably useful polymeric diolefin oil is obtained by adding 75 to 100 parts of butadiene and 25 to 0 parts of styrene in the presence of metallic sodium as a catalyst Reaction brings. The production of this oil in the presence of an alkali metal or peroxide catalyst is in U.S. Patents 2,762,851 and 2,586,594.

In the following examples, unless otherwise noted, all parts and percentages are given based on weight.

example 1

Laminates A, B, C, D, E, F, G and H are made from various mixtures of styrene and m-diisopropenylbenzene (DIPB) (Table I). Each mixture also contains the following compounds:

link Weight percent Natural rubber
Benzoyl peroxide
Dicumyl peroxide 1.6
1
1

Each mixture is used to impregnate 14 layers of glass fabric with applied vinylsilane used. The impregnated fabric is heated to 127 ° C in a hollow mold (3.51 mm) for% hour. The cured fabric is then cut in half. Half of each is put in an air oven post cured at 135 ° C for 1 hour. Samples measuring 12.70 x 76.2 mm were cut from the laminate and tested (also shown in Table I).

It was found that excellent strength was obtained for all of the above laminates when the measurement was made at room temperature. In addition, when using 10% or more diisopropenylbenzene strength at 12O ⁰ C was excellent. The use of styrene in the mixture diisopropenylbenzene also yields cured laminates having at 150 ⁰ C and at even higher temperatures very excellent characteristics. The laminate H had a flexural strength of 3045 kg / cm ^2, which represents a 69% ig ^en preserving the strength, if one uses the strength at ordinary temperature for comparison at 150 ⁰ C. The strength is therefore superior to the strength of more expensive types of resin, such as those used in reinforced plastics.

Table I.

Weight
relationship Post-curing Flexural strength cm ² at Layer- Styrene to DIPB kg /
at 12O ⁰ C ston space tempe 245 97.5: 2.5 no rature 675 A. 97.5: 2.5 Yes 3360 770 B. 95: 5 no 4480 1470 C. 95: 5 Yes 4900 2240 D. 90:10 no 4900 3640 E. 90:10 Yes 4690 2520 F. 80:20 no 4305 3500 G 80:20 Yes 4130 H 4445

Comparative experiments

The procedure is as in Example 1, but various others are used in place of diisopropenylbenzene Monomers.

Table II

Monomer used Weight
percent Bend
strength,
at
about 120 ° C
kg / cm ² Divinylbenzene
Divinylbenzene
Ethylene dimethacrylate
Ethylene dimethacrylate
Trimethylol propane
Trimethylol propane
Diisopropenylbenzene
Diisopropenylbenzene 5
10
5
10
5
10
5
10 665
1540
420
1330
560
1610
1470
3640

Benches were found with regard to the flexural strength at different temperatures:

Used To Flexural Strength, kg / cm ² , at 120 ° C 150 ° C 177 ° C 205 ° C 5 DIPB harden 24 ° C 3570 3570 2240 1470 Meta no 4200 4130 3815 2660 1540 Meta Yes 4095 3955 3385 2800 1890 Para no 4095 3850 3710 2450 1820 IO Para Yes 4235

Table II shows the superiority of diisopropenylbenzene on a high styrene laminate. The flexural strength is 230 to 350% higher at 120 ° C, which is a clear, significant improvement is.

Example 2

The procedure is as in Example 1, except that 2,4-dimethylstyrene is used instead of styrene. Laminates from this styrene homologue and diisopropenylbenzene have quite excellent at higher temperatures Properties.

10 % To 20% To Diisopropenylbenzene harden Diisopropenylbenzene harden shape shape harden harden Flexural strength, at about 3850 3850 120 ° C, kg / cm ² 3745 3640 at about 3115 3605 150 ° C, kg / cm ² 2870 3220

These data demonstrate the excellent strength obtained when using m-diisopropenylbenzene other types of styrene compounds is applied.

Example 3

Although m-diisopropenylbenzene is very useful, the para-isomer is just as or better suited for improving the strength of reinforced plastics with a high styrene content. This is evident from the information below. It provides the following mixture is prepared: 80 parts of 2,4-dimethyl 2 ° / ₀ pale crepe natural rubber, 20 parts of m-diisopropenylbenzene and 1.5 parts of dicumyl peroxide. This mixture is used to impregnate 14 layers of glass fabric with applied vinyl silane. The impregnated fabric is heated for hour at 143 ⁰ C in a cavity mold (3,51mm) Vz. The laminate was cut into two halves, of which one half in an air oven at 15O ⁰ C for 1 hour was post.

A similar laminate was also made, but used in place of the meta-isomer 20 parts of pure p-diisopropenylbenzene. From the pro

Example 4

A mixture is made from the following ingredients:

component

Styrene

Diisopropenylbenzene

Light crepe

Silane (a)

Dicumyl peroxide

Parts by weight

92.5 7.5

1.0

0.25

1.0

(a) A vinyl silane ester of the monomethyl ether of ethylene glycol.

14 layers of glass fabric with applied silane are impregnated with the mixture and ^{heated to 135 °} C. for 1 hour in a hollow mold (3.42 mm). The excellent physical properties are tabulated below: Flexural Strength

at room temperature 4725 kg / cm ²

at 77 ° C 3745 kg / cm ²

at 120 ° C 3080 kg / cm ²

after boiling in water for 24 hours, 3815 kg / cm ²

after boiling in water for one week 3920 kg / cm ²

It can be seen that the use of dicumyl peroxide as a catalyst in a mixture of styrene and diisopropenyl gives a laminate excellent in boiling resistance Owns water.

Example 5

A polymeric oil mixture is produced from the compounds listed below:

1,3-butadiene 80 parts

Styrene 20 parts

Ligroin *) 200 parts

Dioxane 40 parts

Isopropanol 0.2 parts

Sodium **) 1.5 parts

*) Ligroin distilled off directly, boiling range 150 to 200 ° C. * *) With the help of an Eppenbach homomixer to a particle size of 10 to 50 μ. dispersed.

The polymerization was carried out at 5O ⁰ C in a 2-1 autoclave equipped with a mechanical stirrer. Complete conversion was achieved after 4 ^x _1/2 hours. The catalyst was destroyed and removed from the crude product. Almost all of the solvent was removed by distillation and a product having an average molecular weight of about 8,000 was obtained.

The polymer oil and vinyl toluene produced in this way became mixtures in proportion

relationship Post-curing Flexural strength 120 ⁰ C polymeric oil kg / cm ⁸ 2940 to vinyl toluene no 24 ° C - 60:40 Yes*) 4060 1575 60:40 no - 2520 50:50 Yes 4165 1225 50:50 no 4200 2800 40:60 Yes 3535 40:60 3850

60:40; 50:50; 40:60 made. The first two mixtures were supplemented with 5% diisopropenylbenzene and the mixture containing 60% of vinyl toluene with 7V ₂ ⁰ A diisopropenylbenzene. Then 2% dicumyl peroxide and 2% tert-butyl peroxide were added and laminates were produced according to Example 1. Each laminate was heated to 160 ° C. for ^{2 / a hour.} Each laminate was then cut in half, one half of which was post cured in an air oven at 177 ° C for 2 hours. Tests of the laminates showed the following:

IO to improve their strength at 120 ° C, one can use diisopropenylbenzene. 50 mixture, 1750 kg / cm ² for the 40: 60-mixture without the use of diisopropenylbenzene the flexural strength of the cured samples at 12O ⁰ C 2100 kg / cm ² for the 50 would be.

Claims (2)

Claims; 1. A process for the production of copolymers reinforced with glass fibers, characterized in that that glass fibers with a monomeric styrene compound of the general formula CH = CH ₂ 20th *) During post-curing, the laminate broke very severely at a ratio of 60:40 between polymer oil and vinyl toluene at _{2 of the} edges where the glass content was low. Therefore it was not examined further. From the above data it can be seen that the use of diisopropenylbenzene results in a plastic its excessive crosslinking extends to brittleness if the ratio between polymeric oil and vinyl toluene is 60:40 or higher. However, if the hardening is not taken too far, then diisopropenylbenzene is suitable very good for increasing the strength at 120 ° C. To use high styrene mixtures in in which R, R ₁ , R ₂ , R ₃ and R ₄ denote hydrogen or halogen atoms or alkyl radicals with not more than 18 carbon atoms, and a monomeric benzene compound substituted by two or more isopropenyl groups and optionally substituted by halogen atoms or alkyl radicals and the monomer mixture polymerized in a manner known per se. 2. The method according to claim 1, characterized in that in a known manner an unsaturated organic silane added to the monomer mixture or before the treatment with the monomer mixture is applied to the glass fiber. 909533/281