CA1065541A - Removing solvent from elastomers - Google Patents
Removing solvent from elastomersInfo
- Publication number
- CA1065541A CA1065541A CA227,426A CA227426A CA1065541A CA 1065541 A CA1065541 A CA 1065541A CA 227426 A CA227426 A CA 227426A CA 1065541 A CA1065541 A CA 1065541A
- Authority
- CA
- Canada
- Prior art keywords
- composition
- pentane
- solvent
- elastomer
- cement
- 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.)
- Expired
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08C—TREATMENT OR CHEMICAL MODIFICATION OF RUBBERS
- C08C2/00—Treatment of rubber solutions
- C08C2/06—Wining of rubber from solutions
Landscapes
- Chemical & Material Sciences (AREA)
- General Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Processes Of Treating Macromolecular Substances (AREA)
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Extrusion Moulding Of Plastics Or The Like (AREA)
Abstract
A B S T R A C T
A process for the removal of a C6-7-hydrocarbon solvent from an elastomer composition in a devolatilization zone under such conditions of pressure and temperature that the solvent evaporates from the composition, which comprises mixing an amount of a pentane with the composition after polymerization and prior to the evaporation.
A process for the removal of a C6-7-hydrocarbon solvent from an elastomer composition in a devolatilization zone under such conditions of pressure and temperature that the solvent evaporates from the composition, which comprises mixing an amount of a pentane with the composition after polymerization and prior to the evaporation.
Description
~655~L
This învention relates to a process for the removal of a C6 7-hydrocarbon solvent from elastomer compositions in a devolatilizat;on zone under such conditions of press~lre and temperature that the solvent evaporates from the composition.
In the manufacture of synthetic rubber by solution polymerization of a diene a hexane such as n-hexane or cyclo-hexane - often in admixture ~ith pentanes - is usuall~ employed as solvent. Before it can be used, the elastomer product must be desolventized, for which purpose a number of methods have been proposed. Apart from the popular method of steam coagula-tion which is less economical in respect of steam consumption/
more recent techniques involYe flash drying in a flash chamber, or in a ~ented extruder. "Flashing" as used herein indicates evaporation of the volatile solvent after a sudden pressure drop of t~,e composition, e.g. over an expansion nozzle having a constriction at or near its outlet. When the elastomer composition is flashed in a vented extruder, desolventizing may be improved by introducing water or an inext gas as a devolatil-ization aid into the extruder prior to the vent section.
It has now been found that the use of pentanes as devolatilization aid provldes a number of advantages as will be explained héreinafter. The invention may thus be defined as a process for the removal of a C6_7-h~drocarbon sol~ent from an elastomer co~pos;tion in a devolatilization zone under such conditions of press-ure and temperature that the solvent evaporates from the composïtionl which comprises mixing an amount of a pentane with thR composition aftex polymerization and prior ta the e~aporation.
~554~
The elastomers ~hich can be treate.d acc~rding to the invention include various types of synthetic rubber such as polybutadiene, polyisoprene, random or block copolymers of dienes such as butadiene, with s-tyrene, polycyclopentene, chloroprene rub~er, butyl rubber and ethylene/propylene/
dicyclopentadiene ru~ber. The method i5 particularly effective in treati.ng co~positions: compri.sing polybutadiene and copolymers of butadiene and styrene ~h:ich contain more than 5a% ~ of butadiene. The process can be used on elastomers ha~ing a Mooney viscosit~ (ML 1~4 at lQaC) of 10-18~. Compositions containing hIends of eIastomers can also be treated according to the invention~
The C6 7-h~drocarbon solvent to ~e xemoved from the present compositions can be any ali~hati.c, cycloaliphatic or aromatic hydrocarbon having 6 or 7 carb.on atom~ per molecule.
Examples of such solvents are n-hexane, n-heptane, cyclohexane, methylcyclohexane, toluene and benzene or mixtures thereof or ~ith other h~drocar~ons s:uch as pentanes. The process according to the invention is especially effective in treating compositions containing cyclohexane, benzene and/or toluene, usually in admi~ture ~ith pentanes such. as isopentane or cyclopentane.
Unreàcted monomexs- such as ~utadiene or st~rene can also be present in s~all amounts in the compositions to be treated.
The compos~tions may originate from a solution polymerization of the rubber ~ielding ~lonomers in a solYent mixture comprising, e.g., cyclohexane and isopentane in a weight ratio of from lOO~a to 40~60. Th.e rub~er cement obtained as a result o~ the polymerization may haYe a solids (elastomer) content of up to 45% ~, usually between lQ and 35% ~. According to one em~odiment of the invention a pentane devolatilization aid i5 added to the cement, usually ~6~54~
in an amount of up to 100 %w, based on the cement. The diluted cement so obtained may be devolatilized by flash-drying as mentioned above, preferably in a flash chamber. Methods for flashing elastomer cements have been dis-closed in, e.g., UK patent no. 1~330,890 in the name of Bayer A.G. publication date September 19, 1973; 1,209,205 in the name of ~litsui Petrochemical Industries Ltd. publication date October 21, 1970; and 1,197,382 in the name of Firestone Tire and Rubber Co., publication date July 1, 1970. Before flashing o~ the diluted cement, heat is usually introduced via a heat ex-changer. If desired, heat may also be introduced by means of the pentane devolatili~ation aid heated to a temperature of, e.g., 180-220C before addition to the cement.
The invention is particularly applicable to the devolatilization of elastomer compositions obtained after flashing the major part of the solvent from a rubber cement, e.g. by methods disclosed in the above patent specifications. The solids content of the elastomer composition after flashing will in general be above 50 ~w, pTeferably 80-95 %w. Because of the very high viscosity of such compositions, a preferred and practical apparatus for removing the last traces of solvent is a desolventizing extruder.
The elastomer composition is charged into the extruder and me-chanically worked to increase its temperature. A pentane is added tG thecomposition, either prior to or simultaneously with the charging of the com-position into the extruder. Preferably, a pentane is introduced through an inlet in a mixing section of the extruder and is mixed in the said section with the composition. It is possible that upon introduction of larger amounts o~ pentane, a part thereo~ does not dissolve in the composition in the mixing section and may thus act as a lubricant~ preventing the build-up o excessive temperatures. The mixture passes through the extruder and enters a vented section thereof, in which hydrocarbon vapours 55~
are fla~hed from the mixture and escape or are ~ecoyered.
Preferably, the composition i5 subjected to a plurality of mixing/Yenting operat~ons in the extruder to provide greater efficienc~ in removing volatiles.
The amount o~ pentanes to be introduced into the extruder depends on such factors as the type of elastomer, th~
amount and type of ~olatiles to be removed and the temperatures adopted. In general, from 1 1000% of a pentane is introduced, based on the ~eight of residual solvent present in the composition. Pre~erred amounts of pentane~ are in the range 5Q-50Q%.
An~ pentane hydrocarbon may be used as a devola~tiliza-tion aid, such as n-pentane, isopentane, neopentane and cyclo-pentane. Preferred pentanes are n-pentane and isopentane.
Experiments with unsaturated hydrocarbons, such as isopentene or n-pentene, ha~e sho~n that these are less effective as a devolatilization aid, ~hen compared ~ith the corresponding saturated hydrocar~bns.
Temper~tures during deyolatilization according to the 2a invention are primarily dictated by the boiling point of the volatiles, the stahility of the polymers at high temperatures and the limitations of the equipment. High temperatures favour the removal o~ volat~les ~ut it i5 usually undesirable to operate ~ith polybutadiene or ~utadiene~styrene copolymer at temperaturPs much in excess of 200C. Preferred temperatures are ln the ran~e lQQ-2Q~C.
Remo~al of ~olatiles can be accomplished at any suitable pressure, though it is usually advantageous to operate at atmospheric or suhatmospheric pressure, e.~. at a pressure of 3~ Q.Ql-0.8 bar(Rbsl, in particular 0.4-Q.6 bar(abs~. Pressures ~L~65S~
~ill also be determined b~ the conditions under ~hich solvent recovery operations, if any, are to be perfoxmed.
Oil and other compounding ingredients such as anti-oxidants and carbon ~lack can be added to the elastomeric composition either before, during or after the removal of the volatile hydrocarbons. Oil may be added in an amount of 100 or more parts by ~eight tpbw~, preferably 10-6Q pb~, per 100 pbw of elas-tomer. M~xing of the oil during extrusion is effected ~ithout any difficult~. The compounding ingxedients may be dissol~ed in the ~entane aevolatilization aid, or may be added sepa~ately to the co~o~ition. If dissol~ed in the pentane devolatilization ai~d, improved dispersion throughout the elastomer composition ~ill result. ~hen suhstantial amounts of oil are to be added to the elastomer, the use of a second extruder is recommended.
~ The discharge at the do~nstream end of the extruder is ; suitably provided ~ith a die plate cuttex so as to produce eIastomer nibs.
Solvent vapours recovered from the evaporation step may be easily condensed. Due to the choice of pentanes as devolatilization aid an excessively high vacuum or pressure during evaporation and condensation may be avoided. A vacuum of 0.4-0.6 bar(abs~ has been found to be generally ade~uate for the purpose of the invention; still a surprising reduction in C6_7-hydrocarbon solvent content of the composition may be obtained with pentanes. Another advantage of the use of pentanes i5 that the size of the condensors may be relatively small and that deep cooling is not required. Solvent losses to the atmosphere may be reduced to a minimum. The condensate may be recycled as such to the polymerization reactor. By simple 1~55~
fractionation the compositi.on o~ the. recycle stream may be adjusted a5 desired. If water - su~gested by th.e art - is used as devolatilization ai.dr a wet solvent and wet elastomer result which requires separate dry.ing steps. The use of inert gases such as nitrogen requires the use of large condensors and/or deèp cooling.
EXAMpLE
lithium-catal~sed random styrene~butadiene copolymer h.avî.ng a styrene content of 23% ~ and a limiting ~î~cosity num~er of 3 dl~g Cmeasured in toluene at 25C), ~as used in this example. Th.e copol~mer was in the form of a cement in a mixture of 75~25 ~ c~clohexane~i~opentane, the copolymer conient bein~ 25% w. The cement ~as mixed ~l.th. 1% w of a ph.enolic antioxidant ("IONOL"~*, ~ased on copolymer. The cement was heated to 184C and flashed in a ch.am~er in ~h.ich atmospheric : p~essure ~as maintai.ne.d.
Th.e resiulting porous. threads of rubber had a copolymer content of 85% ~, an isopentane content of Q.6~ w and a cyclo-hexane content of 15~ ~. The threads: ~ere fed at a temperature 2a of laOC into a de~olati.li,zing e.xtruder haying three mixing sections and t~o ~ent~.ng sections, the latter secti.ons being kept at a ~acuum of ~.5 bar~abs~. Th.e length.~diametex ratio :~ of the extrudex ~s 20. In the first ~ixing secti,on 53.5 phr ; (~arts b~ ~eight per 100. parts of copolymer~ of isopentane were introduced. In this section the temperature and pressure rose to 144C and 20 bar, respectively. After passing the first venti.ng section the elastomer contained a . 5 phr of cyclohexane and 2.8 phr of isopentane. After ha~ing entered the second mixing~venting sectiQn at 140.C the elastomer composition was 30. again compressed and devolati.lized without adding i.sopentane, *Trade Mark `` !L~f~S54~
however. After the second venting section the elastomer had a solvent content of only 0.5 phr, of which less than 0.05 phr was cyclohexane. Via the final mixing section the elastomer was discharged at the end of the extruder through a die plate, the residual solvent content being less than 0.2 phr.
When no isopentane was added in the first mixing section, the cyclohexane sontent after the first venting section was 3 phr.
This învention relates to a process for the removal of a C6 7-hydrocarbon solvent from elastomer compositions in a devolatilizat;on zone under such conditions of press~lre and temperature that the solvent evaporates from the composition.
In the manufacture of synthetic rubber by solution polymerization of a diene a hexane such as n-hexane or cyclo-hexane - often in admixture ~ith pentanes - is usuall~ employed as solvent. Before it can be used, the elastomer product must be desolventized, for which purpose a number of methods have been proposed. Apart from the popular method of steam coagula-tion which is less economical in respect of steam consumption/
more recent techniques involYe flash drying in a flash chamber, or in a ~ented extruder. "Flashing" as used herein indicates evaporation of the volatile solvent after a sudden pressure drop of t~,e composition, e.g. over an expansion nozzle having a constriction at or near its outlet. When the elastomer composition is flashed in a vented extruder, desolventizing may be improved by introducing water or an inext gas as a devolatil-ization aid into the extruder prior to the vent section.
It has now been found that the use of pentanes as devolatilization aid provldes a number of advantages as will be explained héreinafter. The invention may thus be defined as a process for the removal of a C6_7-h~drocarbon sol~ent from an elastomer co~pos;tion in a devolatilization zone under such conditions of press-ure and temperature that the solvent evaporates from the composïtionl which comprises mixing an amount of a pentane with thR composition aftex polymerization and prior ta the e~aporation.
~554~
The elastomers ~hich can be treate.d acc~rding to the invention include various types of synthetic rubber such as polybutadiene, polyisoprene, random or block copolymers of dienes such as butadiene, with s-tyrene, polycyclopentene, chloroprene rub~er, butyl rubber and ethylene/propylene/
dicyclopentadiene ru~ber. The method i5 particularly effective in treati.ng co~positions: compri.sing polybutadiene and copolymers of butadiene and styrene ~h:ich contain more than 5a% ~ of butadiene. The process can be used on elastomers ha~ing a Mooney viscosit~ (ML 1~4 at lQaC) of 10-18~. Compositions containing hIends of eIastomers can also be treated according to the invention~
The C6 7-h~drocarbon solvent to ~e xemoved from the present compositions can be any ali~hati.c, cycloaliphatic or aromatic hydrocarbon having 6 or 7 carb.on atom~ per molecule.
Examples of such solvents are n-hexane, n-heptane, cyclohexane, methylcyclohexane, toluene and benzene or mixtures thereof or ~ith other h~drocar~ons s:uch as pentanes. The process according to the invention is especially effective in treating compositions containing cyclohexane, benzene and/or toluene, usually in admi~ture ~ith pentanes such. as isopentane or cyclopentane.
Unreàcted monomexs- such as ~utadiene or st~rene can also be present in s~all amounts in the compositions to be treated.
The compos~tions may originate from a solution polymerization of the rubber ~ielding ~lonomers in a solYent mixture comprising, e.g., cyclohexane and isopentane in a weight ratio of from lOO~a to 40~60. Th.e rub~er cement obtained as a result o~ the polymerization may haYe a solids (elastomer) content of up to 45% ~, usually between lQ and 35% ~. According to one em~odiment of the invention a pentane devolatilization aid i5 added to the cement, usually ~6~54~
in an amount of up to 100 %w, based on the cement. The diluted cement so obtained may be devolatilized by flash-drying as mentioned above, preferably in a flash chamber. Methods for flashing elastomer cements have been dis-closed in, e.g., UK patent no. 1~330,890 in the name of Bayer A.G. publication date September 19, 1973; 1,209,205 in the name of ~litsui Petrochemical Industries Ltd. publication date October 21, 1970; and 1,197,382 in the name of Firestone Tire and Rubber Co., publication date July 1, 1970. Before flashing o~ the diluted cement, heat is usually introduced via a heat ex-changer. If desired, heat may also be introduced by means of the pentane devolatili~ation aid heated to a temperature of, e.g., 180-220C before addition to the cement.
The invention is particularly applicable to the devolatilization of elastomer compositions obtained after flashing the major part of the solvent from a rubber cement, e.g. by methods disclosed in the above patent specifications. The solids content of the elastomer composition after flashing will in general be above 50 ~w, pTeferably 80-95 %w. Because of the very high viscosity of such compositions, a preferred and practical apparatus for removing the last traces of solvent is a desolventizing extruder.
The elastomer composition is charged into the extruder and me-chanically worked to increase its temperature. A pentane is added tG thecomposition, either prior to or simultaneously with the charging of the com-position into the extruder. Preferably, a pentane is introduced through an inlet in a mixing section of the extruder and is mixed in the said section with the composition. It is possible that upon introduction of larger amounts o~ pentane, a part thereo~ does not dissolve in the composition in the mixing section and may thus act as a lubricant~ preventing the build-up o excessive temperatures. The mixture passes through the extruder and enters a vented section thereof, in which hydrocarbon vapours 55~
are fla~hed from the mixture and escape or are ~ecoyered.
Preferably, the composition i5 subjected to a plurality of mixing/Yenting operat~ons in the extruder to provide greater efficienc~ in removing volatiles.
The amount o~ pentanes to be introduced into the extruder depends on such factors as the type of elastomer, th~
amount and type of ~olatiles to be removed and the temperatures adopted. In general, from 1 1000% of a pentane is introduced, based on the ~eight of residual solvent present in the composition. Pre~erred amounts of pentane~ are in the range 5Q-50Q%.
An~ pentane hydrocarbon may be used as a devola~tiliza-tion aid, such as n-pentane, isopentane, neopentane and cyclo-pentane. Preferred pentanes are n-pentane and isopentane.
Experiments with unsaturated hydrocarbons, such as isopentene or n-pentene, ha~e sho~n that these are less effective as a devolatilization aid, ~hen compared ~ith the corresponding saturated hydrocar~bns.
Temper~tures during deyolatilization according to the 2a invention are primarily dictated by the boiling point of the volatiles, the stahility of the polymers at high temperatures and the limitations of the equipment. High temperatures favour the removal o~ volat~les ~ut it i5 usually undesirable to operate ~ith polybutadiene or ~utadiene~styrene copolymer at temperaturPs much in excess of 200C. Preferred temperatures are ln the ran~e lQQ-2Q~C.
Remo~al of ~olatiles can be accomplished at any suitable pressure, though it is usually advantageous to operate at atmospheric or suhatmospheric pressure, e.~. at a pressure of 3~ Q.Ql-0.8 bar(Rbsl, in particular 0.4-Q.6 bar(abs~. Pressures ~L~65S~
~ill also be determined b~ the conditions under ~hich solvent recovery operations, if any, are to be perfoxmed.
Oil and other compounding ingredients such as anti-oxidants and carbon ~lack can be added to the elastomeric composition either before, during or after the removal of the volatile hydrocarbons. Oil may be added in an amount of 100 or more parts by ~eight tpbw~, preferably 10-6Q pb~, per 100 pbw of elas-tomer. M~xing of the oil during extrusion is effected ~ithout any difficult~. The compounding ingxedients may be dissol~ed in the ~entane aevolatilization aid, or may be added sepa~ately to the co~o~ition. If dissol~ed in the pentane devolatilization ai~d, improved dispersion throughout the elastomer composition ~ill result. ~hen suhstantial amounts of oil are to be added to the elastomer, the use of a second extruder is recommended.
~ The discharge at the do~nstream end of the extruder is ; suitably provided ~ith a die plate cuttex so as to produce eIastomer nibs.
Solvent vapours recovered from the evaporation step may be easily condensed. Due to the choice of pentanes as devolatilization aid an excessively high vacuum or pressure during evaporation and condensation may be avoided. A vacuum of 0.4-0.6 bar(abs~ has been found to be generally ade~uate for the purpose of the invention; still a surprising reduction in C6_7-hydrocarbon solvent content of the composition may be obtained with pentanes. Another advantage of the use of pentanes i5 that the size of the condensors may be relatively small and that deep cooling is not required. Solvent losses to the atmosphere may be reduced to a minimum. The condensate may be recycled as such to the polymerization reactor. By simple 1~55~
fractionation the compositi.on o~ the. recycle stream may be adjusted a5 desired. If water - su~gested by th.e art - is used as devolatilization ai.dr a wet solvent and wet elastomer result which requires separate dry.ing steps. The use of inert gases such as nitrogen requires the use of large condensors and/or deèp cooling.
EXAMpLE
lithium-catal~sed random styrene~butadiene copolymer h.avî.ng a styrene content of 23% ~ and a limiting ~î~cosity num~er of 3 dl~g Cmeasured in toluene at 25C), ~as used in this example. Th.e copol~mer was in the form of a cement in a mixture of 75~25 ~ c~clohexane~i~opentane, the copolymer conient bein~ 25% w. The cement ~as mixed ~l.th. 1% w of a ph.enolic antioxidant ("IONOL"~*, ~ased on copolymer. The cement was heated to 184C and flashed in a ch.am~er in ~h.ich atmospheric : p~essure ~as maintai.ne.d.
Th.e resiulting porous. threads of rubber had a copolymer content of 85% ~, an isopentane content of Q.6~ w and a cyclo-hexane content of 15~ ~. The threads: ~ere fed at a temperature 2a of laOC into a de~olati.li,zing e.xtruder haying three mixing sections and t~o ~ent~.ng sections, the latter secti.ons being kept at a ~acuum of ~.5 bar~abs~. Th.e length.~diametex ratio :~ of the extrudex ~s 20. In the first ~ixing secti,on 53.5 phr ; (~arts b~ ~eight per 100. parts of copolymer~ of isopentane were introduced. In this section the temperature and pressure rose to 144C and 20 bar, respectively. After passing the first venti.ng section the elastomer contained a . 5 phr of cyclohexane and 2.8 phr of isopentane. After ha~ing entered the second mixing~venting sectiQn at 140.C the elastomer composition was 30. again compressed and devolati.lized without adding i.sopentane, *Trade Mark `` !L~f~S54~
however. After the second venting section the elastomer had a solvent content of only 0.5 phr, of which less than 0.05 phr was cyclohexane. Via the final mixing section the elastomer was discharged at the end of the extruder through a die plate, the residual solvent content being less than 0.2 phr.
When no isopentane was added in the first mixing section, the cyclohexane sontent after the first venting section was 3 phr.
Claims (18)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A process for the removal of a C6-7-hydrocarbon solvent from an elastomer composition in a devolatilization zone under such conditions of pressure and temperature that the solvent evaporates from the composition, which comprises mixing an amount of a pentane with the composition after polymerization and prior to the evaporation.
2. A process as claimed in claim 1, in which the elastomer is a polymer of butadiene.
3. A process as claimed in claim 2, in which the elastomer is a copolymer of butadiene and styrene containing more than 50%w of butadiene.
4. A process as claimed in any one of claims 1 to 3, in which the elastomer has a Mooney viscosity (ML 1+4 at 100°C) of 10 to 180.
5. A process as claimed in claim 1, in which the composition contains cyclohexane, benzene and/or toluene as a solvent.
6. A process as claimed in claim 5, in which the solvent is a mix-ture of cyclohexane and isopentane in a weight ratio of at least 40/60.
7. A process as claimed in claim 1, in which the composition is a rubber cement originating from a solution polymerization and having a solids content of up to 45%w, to which a pentane is added in an amount of up to 100%w (based on the cement), whereupon the diluted cement is devolatilized by flashing in a flash chamber.
8. A process as claimed in claim 7, in which before flashing heat is introduced into the diluted cement.
9. A process as claimed in claim 1, in which an elastomer composition having a solids content above 50%w, obtained after flashing the major part of the solvent from a rubber cement, is further devolatilized in a desol-ventizing extruder, a pentane being added to said composition.
10. A process as claimed in claim 9, in which said composition has a solids content of 80-95%w.
11. A process as claimed in claim 9, in which a pentane is introduced through an inlet in a mixing section of the extruder.
12. A process as claimed in any one of claims 9 to 11, in which the composition is subjected to a plurality of mixing/venting operations in the extruder.
13. A process as claimed in any one of claims 9 to 11, in which 50 to 500% of a pentane (based on the weight of the residual solvent in the com-position) is added to the composition.
14. A process as claimed in any one of claims 1, 7 and 9, in which n-pentane is mixed with the composition.
15. A process as claimed in any one of claims 1, 7 and 9, in which isopentane is mixed with the composition.
16. A process as claimed in any one of claims 1, 7 and 9, in which the temperature of the composition in the devolatilization zone is from 100°C to 200°C.
17. A process as claimed in claim 1, in which the pressure in the devolatilization zone is from 0.01 to 0.8 bar(abs).
18. A process as claimed in claim 17, in which the pressure in the devolatilization zone is from 0.4 to 0.6 bar(abs).
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB2879874A GB1459344A (en) | 1974-06-28 | 1974-06-28 | Removing solvent from elastomers |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1065541A true CA1065541A (en) | 1979-10-30 |
Family
ID=10281353
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA227,426A Expired CA1065541A (en) | 1974-06-28 | 1975-05-21 | Removing solvent from elastomers |
Country Status (9)
| Country | Link |
|---|---|
| JP (1) | JPS5118780A (en) |
| BE (1) | BE830358A (en) |
| CA (1) | CA1065541A (en) |
| DE (1) | DE2528626A1 (en) |
| ES (1) | ES438878A1 (en) |
| FR (1) | FR2276321A1 (en) |
| GB (1) | GB1459344A (en) |
| IT (1) | IT1039455B (en) |
| NL (1) | NL7507598A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS57139107A (en) * | 1981-02-23 | 1982-08-27 | Sumitomo Chem Co Ltd | Separation treatment of copolymer |
| LU86810A1 (en) * | 1987-03-16 | 1988-11-17 | Labofina Sa | PROCESS FOR REMOVING SOLVENT FROM POLYMER SOLUTION |
| WO2017127175A1 (en) * | 2016-01-22 | 2017-07-27 | Exxonmobil Chemical Patents Inc. | High viscosity metallocene polymers with low volatiles content |
-
1974
- 1974-06-28 GB GB2879874A patent/GB1459344A/en not_active Expired
-
1975
- 1975-05-21 CA CA227,426A patent/CA1065541A/en not_active Expired
- 1975-06-18 BE BE1006734A patent/BE830358A/en not_active IP Right Cessation
- 1975-06-26 DE DE19752528626 patent/DE2528626A1/en not_active Withdrawn
- 1975-06-26 FR FR7520086A patent/FR2276321A1/en active Granted
- 1975-06-26 IT IT2482575A patent/IT1039455B/en active
- 1975-06-26 JP JP7866175A patent/JPS5118780A/en active Pending
- 1975-06-26 ES ES438878A patent/ES438878A1/en not_active Expired
- 1975-06-26 NL NL7507598A patent/NL7507598A/en not_active Application Discontinuation
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5118780A (en) | 1976-02-14 |
| FR2276321B1 (en) | 1977-07-08 |
| ES438878A1 (en) | 1977-01-16 |
| IT1039455B (en) | 1979-12-10 |
| FR2276321A1 (en) | 1976-01-23 |
| NL7507598A (en) | 1975-12-30 |
| GB1459344A (en) | 1976-12-22 |
| DE2528626A1 (en) | 1976-01-15 |
| BE830358A (en) | 1975-12-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US3322856A (en) | Method of preparaing diene elastomer/block copolymer composition | |
| DE69210358T2 (en) | Core-shell polymer for use in tire tread | |
| US3683511A (en) | Method of removing volatiles from an elastomer | |
| DE3311449C2 (en) | ||
| US3562204A (en) | Thermoplastic elastomeric composition comprising block copolymers and random copolymers | |
| CA1065541A (en) | Removing solvent from elastomers | |
| FI111851B (en) | A composition comprising a vinyl aromatic polymer and a rubber and a process for its preparation | |
| DE69021360T2 (en) | Styrene-isoprene-butadiene terpolymer rubber and tires with treads made from them. | |
| US2940960A (en) | Process for recovering polymers | |
| DE60128010T2 (en) | Process for the preparation of coupled polymers | |
| DE69017583T2 (en) | High solids solution polymerization. | |
| DE1669734A1 (en) | Rubber compound | |
| DE1745422A1 (en) | Alpha-olefin block copolymers and process for their preparation | |
| NO144215B (en) | ANALOGY PROCEDURE FOR THE PREPARATION OF THERAPEUTIC ACTIVE IMIDAZOLINE / DERIVATIVES | |
| DE4315300A1 (en) | Elastomer for use in the manufacture of compounds for tire treads | |
| US2912401A (en) | Stripping solvent from isobutylene-isoprene copolymer latices | |
| JP7145948B2 (en) | rubber composition | |
| EP0002860A1 (en) | Process for the removal of non-converted monomers from a copolymer of acrylonitrile | |
| US3769256A (en) | Rubbery compositions | |
| DE1795229C3 (en) | Process for the preparation of a polymer mixture | |
| JP4459340B2 (en) | Method and apparatus for recovering a polymer from a polymer solution | |
| DE1921017C3 (en) | Process for the production of rubbery polymers | |
| US2888498A (en) | Production of colorless emulsion-polymerized polymers | |
| US3183221A (en) | Rubbery polymer of a heavy petroleum hydrocarbon, process of making same, and blendsthereof with a rubbery diene polymer | |
| JPH0475244B2 (en) |