A kind of method that reduces permanent deformation of low-learity styrene type thermoplastic elastomer
Technical field
The present invention relates to a kind of method that reduces permanent deformation of low-learity styrene type thermoplastic elastomer, more particularly, relate to the method that reduces type SBS, SIS, m-SBM-S tension set.
Background technology
Generally speaking, the line style styrene analog thermoplastic elastomer can adopt following route synthetic: with the lithium alkylide is initiator, hexanaphthenes etc. are solvent, tetrahydrofuran (THF) is an activator, vinylbenzene or alpha-methyl styrene, divinyl or isoprene are that monomer adopts three-step approach, the segmented copolymer that forms by anionic solution polymerization.
A kind of method of the SBS of reduction set deformation volume is disclosed as Chinese patent CN85 102259B in the prior art, this patent is to adopt to add a small amount of conjugated diene in the first step polymerization process in styrene monomer, but the consumption of conjugated diene is 0.01-5.0% seldom only, is difficult to accurately metering and is difficult for realizing industrialization.Secondly, adopt the set deformation volume of this method products obtained therefrom still bigger, in 16%~44% scope,, be difficult to prepare tension set and be lower than 20% line style styrene analog thermoplastic elastomer product usually 28%~40%.The 3rd, this patent is that alpha-methyl styrene, isoprene analog thermoplastic elastomer do not relate to monomer.
Summary of the invention
The object of the invention is to overcome the defective that exists in the prior art, provide a kind of after preparation line style styrene analog thermoplastic elastomer is finished one section monomer polymerization reactions, adopt two, three sections monomer to add in the reactor simultaneously, be about to conjugated diene monomer (divinyl or isoprene) and add simultaneously with styrene monomer (vinylbenzene or alpha-methyl styrene) and carry out two sections, three sections reactions in the reactor, synthesize tension set and be lower than 25% line style styrene analog thermoplastic elastomer.
The concrete technology contents of the present invention is as follows:
With n-Butyl Lithium or s-butyl lithium is initiator (when n-Butyl Lithium is initiator, should add a small amount of activator such as tetrahydrofuran (THF) etc.), and hexanaphthene or cyclohexane hexane mixed solution etc. is a solvent.After first section vinylbenzene (or alpha-methyl styrene) has reacted, with conjugated diene (divinyl or isoprene), styrene monomer (as vinylbenzene or alpha-methyl styrene) adds together and carries out two sections, three sections reactions in the reactor, and reaction is finished after condense, make the line style styrene analog thermoplastic elastomer after the drying.This product tension set is less than 25%, and other physical and mechanical propertiess of product and former three-step approach are quite synthetic.
The styrene monomer consumption is that the corresponding with it conjugated diene consumption of 15%~40% (is benchmark with the monomer total mass) is 85%~60% in the product of the present invention.
The prepared line style styrene analog thermoplastic elastomer mean number average molecular weight of the present invention is 50,000-200, and 000 polymeric reaction temperature scope: 40 ℃~50 ℃ of one section kick off temperatures, the reaction top temperature must not be above 75 ℃.Two sections, three sections kick off temperatures are 50 ℃~60 ℃, and the reaction top temperature must not be above 110 ℃.Polymerization reaction time: one section reaction times 20min~50min.Two periods, three periods reaction times are 20min~50min.Reaction monomers concentration is 10%~20% (weight percent).
The present invention has the following advantages:
1. simple to operate, two kinds of monomer accurate measurements.
2. the products therefrom tension set is less, below 25%.
3. simple during suitability for industrialized production.
Know-why of the present invention mainly is to utilize styrene monomer and conjugated diolefin monomer to be wanting in apart from obvious at reactivity ratio, and conjugated diolefin monomer polymerization reactions speed is much larger than the polymerization rate of styrene monomer.Two, three sections monomers add fashionable simultaneously, at first reaction mainly is the conjugated diolefin monomer, carrying out along with reaction, the conjugated diolefin monomer concentration is more and more lower, having seldom this moment that weight phenylethylene class monomer and conjugated diolefin monomer generate a bit of random copolymers, is that styrene monomer reacts at last, and this segment random copolymers does not influence the two-phase separating effect of whole product, product has two second-order transition temperatures, and other physical and mechanical properties end of product is influenced.
Physical and mechanical properties according to method synthetic line style styrene analog thermoplastic elastomer provided by the present invention: 300% tensile modulus: 0.8Mpa~8.0Mpa, tensile strength: 5.0Mpa~38Mpa, tensile yield: 650%~1200%, tension set: 4%~30%, shore hardness: 40 Shao A~95 Shao A.
The preparation of specific embodiment 1. line style styrene analog thermoplastic elastomers.
Embodiment 1
Handling clean and with the 5 liter iron stills (band stirs) of nitrogen protection, (or 50m
3Polymeric kettle) in, adds solvent hexanaphthene, vinylbenzene, the tetrahydrofuran (THF) measure, add initiator n-Butyl Lithium (or s-butyl lithium) after still is warming up to 40 ℃~50 ℃.Behind the reaction 30min, vinylbenzene, the divinyl that measures added in the reactor simultaneously, the control top temperature must not surpass 110 ℃, reaction 30min.Termination reaction, discharging add 0.6% 2.6.4 (2.6 1 di-t-butyls, 4-methylphenol) of monomer gross weight, glue after cohesion white polymer, promptly get product after drying.With vinylbenzene, divinyl is that reaction monomers is carried out different vinylbenzene and divinyl proportioning test, and experimental data is listed in table 1.
Table 1
Sequence number | ??S/B | One section vinylbenzene (g) | Two sections, three sections |
Divinyl (g) | Vinylbenzene (g) |
??1A | ??15/85 | ????24 | ????272 | ????24 |
??2A | ??20/80 | ????32 | ????256 | ????32 |
??3A | ??30/70 | ????48 | ????224 | ????48 |
??4A | ??40/60 | ????64 | ????192 | ????64 |
Embodiment 2
Substituting divinyl with isoprene tests.Reaction conditions is with embodiment 1, and experimental data is listed in table 2.
Table 2
Sequence number | ????S/I | One section vinylbenzene (g) | Two sections, three sections |
Isoprene (g) | Vinylbenzene (g) |
??5A | ????15/85 | ????24 | ????272 | ????24 |
??6A | ????20/80 | ????32 | ????256 | ????32 |
??7A | ????30/70 | ????48 | ????224 | ????48 |
??8A | ????40/60 | ????64 | ????192 | ????64 |
Embodiment 3
Substitute vinylbenzene with alpha-methyl styrene, reaction conditions is with embodiment 1, and the experimental data example is in table 3.
Table 3
Sequence number | ??MS/B | One section alpha-methyl styrene (g) | Two sections, three sections |
Divinyl (g) | Alpha-methyl styrene (g) |
?9A | ??15/85 | ????24 | ????272 | ????24 |
?10A | ??20/80 | ????32 | ????256 | ????32 |
?11A | ??30/70 | ????48 | ????224 | ????48 |
?12A | ??40/60 | ????64 | ????192 | ????64 |
Embodiment 4
At 50m
3In the polymeric kettle, be that monomer carries out industrial production with vinylbenzene, divinyl.Temperature of reaction, time, production data was listed in table 4 with embodiment 1.
Table 4
Sequence number | ??S/B | One section vinylbenzene (kg) | Two sections, three sections |
Divinyl (kg) | Vinylbenzene (kg) |
??13A | ??15/85 | ????337.5 | ????3825 | ????337.5 |
??14A | ??20/80 | ????450 | ????3600 | ????450 |
??15A | ??30/70 | ????675 | ????3150 | ????675 |
??16A | ??40/60 | ????900 | ????2700 | ????900 |
Embodiment 5
At 50m
3In the polymeric kettle, be that monomer carries out commerical test with vinylbenzene, isoprene.Working condition is with embodiment 1, and production data is listed in table 5.
Table 5
Sequence number | ????S/B | One section vinylbenzene (kg) | Two sections, three sections |
Isoprene (kg) | Vinylbenzene (kg) |
??17A | ??15/85 | ????337.5 | ????3825 | ????337.5 |
??18A | ??20/80 | ????450 | ????3600 | ????450 |
??19A | ??30/70 | ????675 | ????3150 | ????675 |
??20A | ??40/60 | ????900 | ????2700 | ????900 |
2. the physical and mechanical properties of product test.
The line style styrene analog thermoplastic elastomer that the foregoing description is prepared carries out the physical and mechanical properties test, wherein 300% tensile modulus, tensile strength, tensile yield, tension set are carried out by GB GB/T528-92, and shore hardness is carried out by GB GB/T531-92.Test result is as shown in table 6:
Table 6
Sequence number | Tension set % | 300% tensile modulus MPa | Tensile strength MPa | Pull apart/elongation % | Shore hardness (Shao A) |
??1A | ????8 | ????0.8 | ????6.7 | ????1100 | ????44 |
??2A | ????14 | ????1.0 | ????8.4 | ????1100 | ????58 |
??3A | ????20 | ????2.3 | ????15.4 | ????950 | ????74 |
??4A | ????24 | ????2.8 | ????21.7 | ????750 | ????87 |
??5A | ????4 | ????1.2 | ????12.8 | ????1200 | ????43 |
??6A | ????14 | ????2.0 | ????18.6 | ????1200 | ????53 |
??7A | ????18 | ????2.1 | ????23.1 | ????1100 | ????72 |
??8A | ????24 | ????2.8 | ????31.7 | ????1050 | ????83 |
??9A | ????6 | ????1.2 | ????7.9 | ????1100 | ????41 |
??10A | ????12 | ????1.8 | ????10.3 | ????1050 | ????59 |
??11A | ????20 | ????1.7 | ????15.7 | ????9500 | ????73 |
??12A | ????24 | ????3.7 | ????25.6 | ????680 | ????88 |
??13A | ????6 | ????1.0 | ????7.3 | ????1100 | ????43 |
??14A | ????16 | ????1.3 | ????10.4 | ????1050 | ????56 |
??15A | ????20 | ????1.9 | ????18.1 | ????850 | ????75 |
??16A | ????23 | ????3.3 | ????27.2 | ????700 | ????87 |
??17A | ????8 | ????0.8 | ????15.3 | ????1200 | ????39 |
??18A | ????12 | ????1.9 | ????19.9 | ????1200 | ????48 |
??19A | ????20 | ????2.7 | ????21.3 | ????1100 | ????69 |
??20A | ????24 | ????2.8 | ????32.7 | ????1000 | ????86 |
Comparative example: Comparative Examples 1
The line style styrene analog thermoplastic elastomer adopts original three-step approach production technology to be first section and carries out the styrene monomer reaction, after question response is finished, adds the conjugated diene monomer reaction again, adds styrene monomer at last again and reacts.Other condition is with embodiment 1, and experimental data is listed in table 7, and the physical and mechanical properties test result is listed in table 8.
Table 7
Sequence number | ????S/B | One section vinylbenzene (g) | Two sections divinyl (g) | Three sections vinylbenzene (g) |
??1B | ??15/85 | ????24 | ????272 | ????24 |
??2B | ??20/80 | ????32 | ????256 | ????32 |
??3B | ??30/70 | ????48 | ????224 | ????48 |
??4B | ??40/60 | ????64 | ????196 | ????64 |
Table 8
Sequence number | Tension set % | 300% tensile modulus MPa | Tensile strength MPa | Pull apart/elongation % | Shore hardness (Shao A) |
??1B | ????28 | ????0.6 | ????5.6 | ????1100 | ????40 |
??2B | ????36 | ????1.2 | ????6.7 | ????1000 | ????59 |
??3B | ????40 | ????1.8 | ????13.7 | ????900 | ????75 |
??4B | ????56 | ????19.6 | ????2.3 | ????650 | ????87 |
Comparative Examples 2
Adopt patent CN85 102259B method, adding the conjugated diene amount in one section reaction is (0.5% weight ratio), and other condition is with embodiment 1, and experimental data is listed in table 9, the physical and mechanical properties test result is listed in table 10.
Table 9
Sequence number | ??S/B | One section vinylbenzene (g) | Two sections divinyl (g) | Three sections vinylbenzene (g) |
??1C | ??15/85 | ????24 | ????272 | ????24 |
??2C | ??20/80 | ????32 | ????256 | ????32 |
??3C | ??30/70 | ????48 | ????224 | ????48 |
??4C | ??40/60 | ????64 | ????196 | ????64 |
Table 10
Sequence number | Tension set % | 300% tensile modulus MPa | Tensile strength MPa | Pull apart/elongation % | Hardness (Shao Shi) |
??1C | ????16 | ????1.0 | ????6.0 | ????1100 | ????39 |
??2C | ????24 | ????1.1 | ????8.3 | ????1100 | ????57 |
??3C | ????30 | ????1.9 | ????14.9 | ????900 | ????73 |
??4C | ????40 | ????3.7 | ????20.8 | ????600 | ????89 |
Contrast table 6,8,10 as can be known, under equal conditions prepared permanent deformation of low-learity styrene type thermoplastic elastomer is lower than in addition two kinds of line style styrene analog thermoplastic elastomers that method is prepared according to the present invention.Other physical and mechanical properties is roughly suitable.
The made line style styrene analog thermoplastic elastomer of the present invention is carried out second-order transition temperature (Tg) to be measured.Data are listed in table 11
Table 11
Sequence number | 1A | 2A | 3A | 4A | 5A | 8A | 15A | ?19A |
?Tg1 | -88 | -90 | -87 | -85 | -90 | -88 | -87 | ?- |
?Tg2 | 87 | 89 | 92 | 90 | 84 | 85 | 90 | ?87 |
As shown in Table 11, adopt the prepared line style styrene analog thermoplastic elastomer of the present invention, still have tangible two-phase separating effect.