CA1276381C - Process for the manufacture of elastomers in particulate form - Google Patents

Abstract

ABSTRACT
A process and plant are disclosed for the manufacture of particulate or liquid elastomeric polymers suitable for the manufacture of a wide variety of commercial elastomers, substantially in the absence of water for purifying and particulating the elastamer.

Description

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PROCESS FOR I~E ~ANUFACrURE OF EIASTOMERS
IN PAR~ICU~TE FORM

~ACKGRCUND OF l~E INVE~TICN
, 1. Field of the Invention The present invention relates to a process for manufacturing many of the common ccmmercial elastomers. The elastomers that can be manufactured by this process include, but are not limited to, ethylene-propylene-die~e rubber, styrene-butadiene rubber, styrene-butadiene the~plastic rubber, cis-polybutadiene ru~berl butyl rukker and cis-polyisoprene rubber. The process applies to both batch a~d continuous manufacturing processes. Furtherl the process is used with elastomers prcduced in solution or in particulate form. A
modification of the process makes it applicable for the manufacture very low molecular weight liquid polymers.

2 scription of the Prior Art.
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The manufacture of elastomers in anhydrous solvents or diluents consists of a polymerization section, a catalyst rem~val section, an elastom~r particwlation section, a diluent and monomer recycle purificaticn section and an elastomer packaging and shipping section.
See, for exa~ple for unrelated types of processesJ U.S. Patent 3,',23,929, entitled "Olefin Poly~rization Process", issued Aug. 11, 1~70, to J.L. Paige et al; U.S. Patent 2,565,960, entitled "Preparation of an Improved ~ydrocarbon Resin", issued Aug. 28, 1951, to J.D. Garber et al; U.S. Patent 4,068,053, entitled "Me~hod of Removing Water From Li/~d Olefin In The Polymerization of Olefins", issued ~an. 10, 1978, to C.D. Miserlis et al.
E~istLng elastcmer processes do not normally use fine molecular sieve removal steps prior to the xeactor in the poly~erization section, although ~he use of m~lecular sieves is known in the art. Various purification steps for other processes unrelated to the elastomer process of this invention ~re shown in the prior art. See, for example, U.S. Patent 2,900,430, entitled "Prccess For the Removal of straight Chain A oe tylene Frcm Isoprene", issued ~ug. 18, 1959, to A.M. Henke et : t i~, ~.2~ 3~
al; Uni-ted S-tates Paten-t 2,~06,795, entitled "Recovery and Utilization of Normally Gaseous Olefins", is.sued September 29, 1959, to W. P. Bullard, et al; United States Patent 3,209,050, entitled "Purification of Diolefins", issued September 28, 1965, to E. S. Hanson; Uni.ted States Patent 3,326,999, entitled "P~lrification of Olefins", issued June 20, 1967, to ~. D. Rhodes, Jr.; United States Patent 3,352,840, entitled "Removal of Deposits From Polymerization Reactors", issued November 14, 1967, to C. M. Oktay; Unlted S-tates Patent 3,514,426, entitled "Process For Suppressing Molecular Jump", issued May 26, 1970, to R. E. Barrett; United States Patent 3,635,931, entitled "Polyisoprene From Amylenes Via-Amylene Isomerization Oxidative Dehydrogenation Extractive Distilla-tion and Polymerization of Low-Concentration Isoprene", issued January 18, 1972, to J. W. Davison; United States Patent 4,016,349, entitled "Process for Removing Vanadium Residues From Polymer Solutions", issued April 5, 1977, to J. M. McKenna;
United States Patent 4,182,801, entitled "Method of Drying Liquid Olefin Monomer Feed in a Molecular Sieve Dryer in the Polymerization of Olefins From Liquid Olefin Monomer", issued January 8, 1980, to ~iserlis, et al; United States Patent 4,235,983, entitled "Purification o:E Olefin Recycle to Poly-merization"~ issued November 25, 1980, to Steigelmann, et al;
and Paige. ~.
Existing processes utilize an expensive hot water injection particulation section which also increases the cost of diluent and monomer recycle purification and adds a water waste disposal problem.
'rhe use of flassling or settling zones Eor recovery of materials in processes unrelated to the elastomer process : .

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~.2 7~,38~ 10677-4 of this inven~ion is also known in the prior art. See, for example, United Sta~es Patent 2,921,053, entitled "Recovery of Olefins From Hydrocarbon Mixtures", issued January 12, 1960 to R. F. Dye; and McKenna.
Further, some patents show the use of additives or product separation. See, for example, U. S. Patent 4,098,980 to Markle, et al. As set out infra, the reactants and other materials are carefully specified, and no additional additives, or place from which they could be in~roduced, are shown in the specification, and the process operates as shown and without any such additives.
SUMMARY OF THE PRESENT INVENTION
The present invention provides apparatus for the manufacture of rubber from a variety of feeds, comprising:
feed means for selecting a subset o the variety of feeds and conveying said suhset of the feeds;
reaction means for receiving said subset from the feed means and for reacting the feeds to produce a product mixture;
- 20 product separation means for receiving said product mixture and separating said product from the other componen~s of said mix~ure by densit~ separation.
The present invention also provides a process for the manufacture of rubber, comprising:
A. providing feed s~ock;
B. reacting the feed stock to produce an effluent of a rubber product and other components;
C. separatiny the rubber product and other components by settling;
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D. evaporating the effluent of Step C to separate the rubber produc~ from o~her components.
By employing the apparatus and/or proces~ o~ the present lnvention, many rubbers can be produced by the same equipment. The rubbers lnclude, fnr example, styrene-butadlene rubber, ethylene oxide-epichlorohyclrin rubber, styrene-butadiene ~hermoplastic rubber, cis-polybutadlene, cis-polyisoprene, ethylene propylene-diene rubber, thermoplastic ethylene-propylene rubber and butyl rubber.
lQ The present invention eliminates several costly portions of the rubber processes of the prior art. The process of the presen~ invention may involve passing the reactan~s through fine molecular sieves to remove impurities prior to the reaction stage and then reacting same.

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Af-ter the reaction sta~e ancl prior -to separating the elastomer and diluent or solvent, it is necessa:ry to re-duce catalyst and monomer concentration in the reactor ef-fluent. With a slurry system, this is accomplished as part of this invention by flowi.ng the reactor effluent to near the middle of a column and flowing fresh diluent from the bottom of the column. The particles are allowed -to settle in the fresh diluent and discharge with the fresh diluent to : the fl.ash separation ~mi-ts discussed supra. The liquid from the reactor effluent flows out of the top of the column.
The present invention also eliminates the costly water injection particulation step and disengages the solvent or diluent directly from dissolved or particulate elastomer .
by flashing the solvent or diluent as vapor and separating particulate elastomer in a flash drum or cyclone.
The elastomer is then finish dried in a fluid bed dryer, packaged and shipped.
The vapor is compressed, condensed to liquid, puri-fied as needed and recycled.
Alternately, ln the case of an elastomer in solu-tion, catalyst reduction is accomplished by contacting the solution with catalyst complexing agents which form high : density insoluble complexes that are separated by decanta-tion or centrifugation. The clarified solution is then sep-arated into particulate elastomer and solvent vapor by flash-ing in a heated pipe and separated in a flask tank or cyclone as above.
BRIEF DESCRIPTION OF THE DRAWINGS
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Fox a further understanding of the nature and ob-jects of the present inven-tion, reference should be had to .

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the :Eollowing detailed description, taken in conjunction with the accompanying drawlngs, in which like parts are given like reference numerals, and wherein:
Figure 1 is a functional block diagram of the elastomer process of the preferred embodiment of the present invention, Figure 2 is a schematic of the elastomer process of the preferred embodiment of the present invention; and ::

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FicJure 3 ls a sch~matic of an alternate confiyuration of the preferred embodiment o~ the present Lnvention showing the process opera-ting on an elastomer in solution with a catalyst removal ~rom solution step; and Fi~ure 4 is a schematic of an alternate configuration of the preferred embodiment of the present invention for liquid elastomer showing the process decanting of liquid elastomer from diluent and catalyst, then stripping the remaining solvent or diluent from the liquid elastomers.
~ CRIPTION OF THE PR~FERRED EMBODI~ENT
As shown in Figure 1, one preferred embodiment of the process of the present invention includes eight major steps, feed preparation and metering 10, reaction ~0, product purification 30, product separation 40, compression 50, diluent purification 60, product drying 70 and product finishing 80.
- Feed Preparation and Metering -Referring to Figure 2r in feed preparation step 10, there are multlple streams. The diluent or solvent stream 101 --flows sequentially through a set of purification columns 103, 105. Column 103 is packed with 3A molecular sieves which reduce `. moisture in the stream by adsorption to less than one part per million. Column 105 is packed with 13X molecular sieves which reduce oxygenated and acetylenic compounds in the stream by ; adsorption to less than one part per million. Compounds that may be adsorbed by the 13~ sieves include any traces o~
alcohol, ketones, carbon monoxide, carbon dioxide, oxygen and : acetylenic compounds. Reduction of these materials in the stream to near zero reduces catalyst requirements and, possibly, by-products which in turn improves post-reactor purification systems.
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~.2~3~1 70677~4 The adsorption columns 103, 105 are constructed of low carhon steel to pressure and temperature specifications in the range of lO0 to 500 psig and 300 to 600F. The columns 103, 105 are regenerated by a heat purging cycle, not shown, and are sized for optimum economic operation.
The preferred diluent 101 for most systems which produce rubber in particulate form in the reactor is isobutane except for (i) ethylene-propylene-dielle rubber, where the preferred diluent is propylene, one of :

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the monomers, and ~ii) butyl rub~r where the preferred diluent is methyl chloride. Also, when cis-polybutadiene or cis-polyisoprene is produced as a solution in the r~actor, the preferred solvent is cis-butene-2. Alternative diluents are propane, n~butane, and pentanes.
Also, depending on the catalyst, propylene, butene-l, trans-butene-2 and pentene may be used as diluents.
The flow through columns 103, 105 to the reactor system 106 is controlled by a flow control loop 104 downstream from the column 105.
Monomer streams 107, 109 are also introduced to the reactor 106 for reaction step 20. These streams 107, 109 are as follows for the several products of this process:

Stream 107 Stream 109 Styrene-Butadiene Rubber Butadiene Styrene St~rene-Butadiene Block Rukber Butadiene Styrene Ethylene~PrGpylene-Diene Rubber Ethylene Ethylidene Nor~ornene Cis-Polybutadiene Rubber Butadiene nil Cis-P~lyisoprene Rubber Isoprene nil Epichlorhydrin Rukber Epichlorohydrin Ethylene oxide Butyl Rubber Isobutylene Isoprene Stream 107 is purified in columns 111, 113 connected in series, and stream lO9 is purified in columns 115, 117 connected in series. Columns 111, 115 are packed with 3A molecular sieves which reduce moisture in these monomers by adsorption to less than one part per million. Columns 113, 117 are packed with 13X molecular sieves which reduce oxygenated and acetylenic ocmpounds in these strean~s to less than one part per million~
The four ads~rption columns 113, 115, 117, 119 are made of low carbon steel to pressure and temperature specification in the range of 100 to S00 psig and 300 to 600F depending on the products to be manufactured at the plant. The columns 113, 115, 117, 119 are regenerated by a heat purge ~ycle, not shown, and are sized for optimum econo~ic operation.

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m e flow through columns 113, 115 is controlled by a flow control lcop 119 that is reset or cascaded from an on-line process analyzer 121, by control loop 123. Analyzer 121 receives samples rom the vapor line 125 between reactor 127 and vapor condenser 129. m is system is satisfactory for volatile monomers such as butadiene, isoprene, ethylene and propylene. Alternatively, stream 107 feed oontrol could be reset or cascaded ~y oDntrol loop 131 from the on-line analyzer 133 which is shown resetting or cascading the flow control loop 135 for stream 109 through columns 115, 117 to the reactor system 106.
~ tream 137 is a hydroge~ stream. This stream is dried in column 139. Column 139 is packed with 3A molecular sieve which reduce moisture in the hydrcgen by adsorption to less than ~ne part per million.
Hydrogen flow through column 139 is controlled by a flow control loop 141. The flow rate is set on the basis of product molecular weight.
Alternatively, the on-line process analyzer 121 may be used to reset the flow control based on hydrogen in the reactor vapor 125.
Hcwever, that relationship is a function of product molecular weight.
Stream 143 is the aluminum alkyl catalyst component that is us~d for ethylene-propylene-diene rubber, cis-polybutadiene rubber, ci~-polyisoprene rub~er, epichlorohydrin rubber and but~l rubber.
Me~erin~ pump 145 is shcwn in Fig. 2 controlling the flow of this ~ onent to either reac*or 127 or reactor 147 depending on the product.
Alternatively, a separate pump may be used for each reactor. A
stainless steel diaphr~m metering pump is normally used for this selvioe.
; Stream 149 is a mcdifier or muxture of mndifiers to optLmize catalyst effectiveness by m~derating the catalyst component reactions or by preventing post reactions of the polymer. Mbter~lg pump 151 controls the flow of stream 149 to reactor 127 or 147 depending on the prcduct.
Alternatively, indiviclual pumps may bc used for each ~odifier and/or for each reactor. A stainless steel diaphrc~m metering pump is normally used for this service.

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Stream 153 is the key oatalyc;t component, and flow is controlled by the stainless steel diaphram metering p~unp 155. I~s component varies depending on the product and n~ay be a cobalt salt, a titarlium salt, a vanadium salt or butyl lithium. A process using butyl lithium normally does not require aluminum alkyl components or mcdifiers.
Streams 101, 107, lO9, 137, 143, 149 are shown in Fig. 2 being mixed in-line as stream 157 or stream 159 to the reactors 127, 147 respectively. mese streams could alternatively enter the bottom of the reactors 127, 147 individually, however in this scheme a m~re uniformly mLxed feed is obtained for entry into the reactors 127, 147. For the use of both reactors 127, 147, an alternate stream 152 is used to intrcduce a moxed in-line stream to reactor 127 directly.
The key catalyst component stream 153 must enter the reactor 127 ~or a stream 154 entering reactor 147 if both reactors of the preferred embodineat are used) separately to prevent reaction before the reactor(s).
- Reaction -Tw~ reactors are shown in Figure 2 since tw~ or three reactors are necessary to produce block polymers such as the styrene-butadiene block ruhber~ A single reactor may be used to produce homopolymers c~nd random coyolymers, hcwever for product quality flexibility, it may be desirable to operate two reactors in parallel or in series. It should be understood that the number of reactors is not a limitation for the invention.
Fig. 2 shc~s ebullient or reflux cooled reactors 127, 147 connected by gravity stream 160. Plternatively an auto-refrigeration system may be used to recycle condensable vapors. Also, alternatively a pipe loop or various other types of reactors may be used. The reactors 127, 147 should have a very high finish surface to minimiz~ sticking of rubber particles to the reactor wall. Such a finish may be achieved by polishing stainless, electro-polishing and possibly coatin~ the surface of polished carbon steel with electro-less m cke~ or a hard teflon ~ 2'7 Fi~

surface. Also b~ffles should not protrude above the operatiny level in the reaetor.
Eaeh reflux stream, stream 161 for reactor 127 and stream 163 for reactor 147, is sprayed into the top of the respective reactor, all to minimi2e stieking of p~rtieles.
An axial turbine agitator, agitator 165 for reaetor 127 and agitator 167 for reaetor 147, is used to mix the reactants and suspend the product partieles.
The pressure and temperature specifications for eaeh reaetor 127, 147 range from 150 to 500 psig and 300 to 550~F depending on the product or products to be manufaetured.
e vapor effluent frc~n eaeh reactor 127, 147 flaws to a condenser, condenser 169 for reaetor 127 and c~ndenser 171 for reactor 147, via vapor streams 125, 173, respeetively. In the eondensers, the condensibles of the vapors are liquified. The non~eondensible gases are reeycled via a reeyele stream, stre~n 175 for reaetor 127 and stream 177 for reactor 147, by a blower, blower 179 for reaetor 127 and blawer 181 ; for re~etor 147, to the bottom of each reactor, reactors 127, 147 respeeti~ely. m e liquified materials, such as the liquid reflux fm m streams 161, 163 are pumped by a pump, pump 183 for reac~or 127 and pump 18, for reaetor 127, through a spray ring in each reactor, ring 187 for reaetor 127 and r m g 189 ~or reactor 147. A stream 191 is provided to vent a portion of the vapor recycle stream 175 to disposal, not shown, automatlcally upon the rise of pressure on reaetor 127 ~eyond a set po1nt detenmined by a pressure control loop 193.
; The simplest mode of operation is for the manufaeture of homopol~ners and random copol~ners using only reaetor 127. In this mLde the eo~bined stre~m 157 and the key eatalyst eomponent stream 153 flow into the reaetor 127, and the rubber slurry discharges from the side of the reaetor 127 as stream l9S to the wash eolumn 197.
For bloek copolymer, th~ combined stream 159, with only one monomer and an alternate key catalyst aomponent stream 154, flow into reaetor 147. The seeond monomer stream 152 flows to the seeond reactor 127.
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Since the reac-tors 127, 1~7 are at the same pres-sure, reactor 147 discharges by yravity through stream 160 to reac-tor 127. Reac-tor 127 discharges via stream 195 to wash column 197 as before. In both modes the level con-trol loop 199 provided on reactor 127 opera-tes the discharge valve 201 on the bottom of the wash column 197 to maintain level in the reactors.
-Product Separation From Reactor Effluent-The slurry from the reactor 127, stream 195, enters the countercurrent wash column 197 about one-half to two-thirds of the distance from the bottom of the column 197.
The key design parameters of the settling column 197 are the ratio of liquid wash to liquid reactor effluent and the ; settling rate of the particles. The volumetric ratio of settling liquid to reactor effluent liquid must be greater than one to insure that the reactor effluent liquid dis-charges at the top of the column 197 as stream 203 under control by pressure control loop 205 goes to a purification section, not shown, and is ultimately partially recycled to stream 101 and partially recycled to column 197. The preferred ratio is 1.25 to 1~75. The column 197 diameter is designed such that the upward flow does not exceed the particle settling rate with a preferred range of 2 to 7 feet per second for most elastomers. The liquid stream 207 .
is pumped to the bottom of column 197 by pump 209. The flow : :
is controlled by a flow control loop 211 which is reset or cascaded by control loop 213 from the density controller sensor, analy~.er 215.

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Alternatively, as shown in Figure 2, a portion of stream 203 may be recycled via stream 206 directly to reactor 147 of the reaction s-tep 20 under control of :Elow control loop 208 to conserve catalyst and energy.
The bottom of column 197 discharges -the elastomer particles in fresh diluent as stream 217. For discharge from column 197, Figure 2 shows an intermittently discharging three-way valve 201 operated by an open-closed position timer 219 that is actuated by the reactor 127 level control 199. A gaseous stream 221 is recycled, as discussed infra, to provide adequate velocity in stream 217.
Figure 2 shown a cone bottom 225 for the column 197. A number of alternate discharge configurations may be posslble or even necessary. Alternatively, -the column 197 bottom section may be agitated or the column 197 mounted on an agitated vessel.
Also the three-way valve 201 shown may be replaced by a vane pump, a moyno pump, a continuously rotating plug, or perhaps even a simple control valve depending on the size of the flow and the characteristics of the slurry.
The surface of column 197 may be made of highly polished stainless s-teel or electroless nickel coated car-bon steel to minimize sticking of particles. The pressure and temperature specification depend on the product manufac-tured and diluent used but will usually range from lS0 to 500 psig and 300 to 550F, respectively, ; ~s shown in Figure 3, when the reactor effluent in stream 195 is a solution, the settling column 197 is by-passed. If catalyst removal is needed, Figure 3 shows stream 195 flowing to a mixer 226 where small amounts of catalyst complexing agents from stream 228 via metering pump 230 are . . .. . . .
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incorporated and reacted. The solution then flows to a pair of hydrocyclones 227, 227A, or centrifuge, to separate the denser catalyst complex. The clariEied polymer solu--tion is then discharged as stream 217 into the flash tube 229 under pressure control of valve 201 by pressure control loop 232, rather than level control loop 199.
Waste :Erom cyclones 227, 227A is accumulated in waste tanks 232, 232A, respectively, and is fed to waste disposal (not shown) via stream 230 controlled by level con-10 trollers 234, 234A, respectively. In addition, no flow is permitted through control loop 211 and recycle from stream 207 all goes to stream 101 via stream 246.
The manufacture of liquid elastomer using another alternate configuration of Figure 4 requires a different modification of the process. A diluent is selected which is not a solvent for the liquid polymer. The effluent of the reactor 127 flows via stream 195 to a decanter 224. In decanter 224, the liquid elastomer settles and is discharged from the bottom of decanter 224 to an agitated film evapo-20 rator 238 or a falling film dryer (not shown) via stream 248. The flow of fluid from decanter 224 is controlled by interface controller 240. The remainder of the fluid in de-canter 224 is diluent and flows via stream 203 to purifica-tion. The vapor from film evaporator 238 flows to filter 237 via stream 235. The liquid from film evaporator 238 flows to storage (not shown) via stream 242. In addition, no flow is permitted through control loop 211 and recycle from stream 207 all goes to stream 101 via stream 246. Al-ternately, the liquid elastomer could be discharged from the bottom of decanter 224 to the flash tube 229.

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-Diluent Purl$ication-The purifica-tion system is not shown in Figure 2 but would consist o:E a di.sti:llatio:n sys-tem -that removes low boiling and high boiliny components and recycles via s-tream 2~3 the major center cut partly to the wash column via Elow control 211 and the remainder to the begi.nning of the pro-cess as part of stream 101 via stream 246 under control of level control loop 244 which controls the level on vessel 245.
-Product Separation-In either the configwration of Fugure 2 or Figure 3, the diluent or solvent 217 is flashed at the discharge valve 201 by flash tube 229. Depending on the solids con-centration, diluent and flash temperature, about one-half to two-thirds of the liquid is vaporized instantaneously.
The flash tube 229 i.s a heat jacketed pipe connected between the valve 201 and flash tank 233. The pipe diameter is de-signed by provide a velocity of at least 3200 feet per minute (53 feettsec) to convey the particles without sticking to the flash tank 233. The length of the flash tube 229 is de-signed to vaporize the remainder of the diluent and heat the elastomer to the required temperature by providin~ sufficient heat transfer surface and is a function of pipe diameter, the desired rubber temperature and thus the amount of heat to be transferred. As shown in Figure 2 and discussed supra, for the concentrated slurries of this invention, some addi-tional gaseous diluent is recycled by stream 221 to acheive the necessary gas to solid ratio ~or dilute phase pneumatic conveying through the flash tube 229.

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The ~as and par-ticula-te rubber ~rom the flash tube 229 enter the flash tan~ 233 -throucJh nozzle 23L where the gas and particulate are separatec1. The flash tank 233 is designed -to provide efficient cyclonic separation.
- Compression -The gas from tank 233 exits tank 233 via stream 235and is filtered by filter 237 and compressed by compressors 239. Some of the gas is recycled from the first stage of compressors 239 via stream 221 for flash tube conveying.
The majorlty of the gas is condensed after compression by condensor 241, collected, and mixed with additional diluent from purification stream 243 in vessel 245. The effluent from vessel 245 is pumped to column 197 as wash liquid stream 207 using pump 209, as discussed supra and excess is mixed with supply stream 101, via level controller 244.
The particulate rubber is discharged fromthe bot-tom of tank 233 via a double trap door type valve 247 to the fluid bed dryer 249.
The flash tank 233 is constructed of aluminum or ~; 20 stainless steel and polished to a hi~h finish and may be coated with electroless nickel to minimize sticking of rub-ber particles. Flashing pressure is in the range of 1 to 10 psig, and temperatures depend on the required particle temp-erature to prevent agglomeration and other sticking of parti-cles. This temperature ma~ range from -50 to 50F.
The remaining diluent gas and liquid, estimated at perhaps 2%, is removed in the fluid bed dryer 249, using closed loop nitrogen s-tream 251 as the fluidizing gas.

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Figure 2 does not show the carbon or molecular seive adsorption system used to remove hydrocarbon from the nitrogen to maintain a reasonable concentration of hydro-carbon in the nitrogen yas, but this is well known in the art.
- Product Finishing -- 13a -o ~, . , . , :
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The particulate rubber is clischar~ed to the pneu-matic conveying system from dryer 249 -throu~h -the double trap door type valve 253 to s-tream 255 for pneumatic con-veying product ~inishing step 80. The conveying medium for tle pneumatic conveying system is air which enters the pro-cess through filter 257. The air picks up the rubber parti-cles at the venturi injector 259, and transports the parti-cles via stream 261 to the cyclonic separa-tion-collector 263.
The motive force for this system is provided by a blower 265.
The particles are discharged from the collector 263 via a double trap door type valve 267, where it goes to a baler (not shown).
- Parameters -The choice of a diluent or solvent is very im-portant to this process. The diluent or solvent should have a relative low boiling point to allow complete vaporization from the elastomer at a temperature at which the elastomeric particles are not sticky. This temperature is controlled by a heated flash tube 229 ahead of the flash chamber 233 and of course the choice of diluent or solvent. Obviously, the ..
diluent solubility characteristic relative to the polymer must be such as to produce particulation in the reactor.
Thus the diluents or solvents are limited to C3, C4 and C5 hydrocarbons and Cl chlorinated hydrocarbon in most cases, in these ionic catalyst polymerizations. Examples of such diluents are propylene in ethylene-propylene-diene and methyl chloride in butyl rubber polymerizations. This invention includes the use of cis-butene-2 and mixtures of cis-butene-2 with trans-butene-2 or butene-l and other C3, C~ and C5 ' ~ 2'~63~33L
hyclrocarbons as a solvent ~or ci.s~polybutadiene, styrene-bu-tadiene and cis-polyisoprene in app:L:ication to the pro-cess of thls invention. Further, this i.nvention conceives the use of C3, C4 and C5 hydrocarbons other -than cis-butene-2 and cis internally unsaturated C5 olefins as diluents for producing cis-polybutadiene, cis-polyisoprene and styrene-butadiene random and block copolymer in particulate form.
A very important factor in producing quality cis-polybu-tadi.ene, cis-polyisoprene, styrene-butadiene and ethyl-ene-propylene-diene elastomers ~ ~q ~ - 14a -: ~ - , . . .
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in particulate ~orm with the usual metal-oryanic catalysts is -to add a modifier that minimizes or prevents cross-linking reactions. Such modi.fiers are well ]~nown as Lewls bases.
Examples of the modifiers are ethers, tri alkyl amines and dialkyl sulfides.
Another important feature of this process is the use of electro-polishing or electroless nickel or teflon to coat the surfaces of critical equipment to minimize or prevent adhesion of elastomer. Equipment that may be coated in this manner includes the reactors 127,147, the transfer lines, the settling column 197 and the flash tank or cyclone 233.
Example 1 ~ `
A solution of 70 wt~% butadiene - 30 wt. % sty-rene mixture at 30% concentration in isobutane is passed through the 3A and 13X molecular sieves in sequence to eliminate dissolved water and actylenic ana other organic catalyst poisons. This stream and a n-butyl lithium stream are separately metered to an autoclave reactor. The re- -actor is equipped to remove the heat of polymerization by the method of evaporating, condensing and recycling conden-sate to the reactor. This method is commonly known as ebul-lient or reflux cooling. rrhe conversion of butadiene and styrene to styrene-butadiene rubber gives a slurry of this rubber in isobutane. The size of the particles in the ` slurry is about 1/16" to 1/4", depending on the degree and quality of agitation and the diluent composition. The re-actor is equipped with a liquid level control that contin-uously discharges an increment of the slurry. The slurry passes to a settling column where the particles drop into '~ - 15 -. . .................... . . ..
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fresh :isobutane and the fluiA from the reactor is discharged :Erom the top of -the column. The settling column thus separ-ates the particles :Erom the unreacted styrene and butad:i.ene.
The fluid from the top of the settling column may be parti-ally recycled to the reactor to conserve s-tyrene-butadiene and catalyst and the remainder is sent to a purlfication section. The slurry from the bottom of the settling column is discharged through a flash heater tube wherealmost all the isobutane is vapori~ed, separated from the particles in a flash tank, compressed, condensed, and recycled to the settling column. The temperature of flashing is controlled at a sufficiently low temperature to prevent stickiness of ` the rubber particles.
The rubber particles are discharged onto a closed-loop nitrogen gas fluid bed dryer which removes residual hydrocarbons. The rubber particles arepneumatically con-veyed to a baling and packaging line.
Example 2 - The same process is used to manufacture styrene-- 20 butadiene-styrene and styrene-isoprene-styrene block copoly-mers except that three reactors is series are used. A 15 wt.% solution of styrene in propane is continuously fed through 3A and 13X molecular sieves sequentially into the first reactor along with a separate stream of n-butyl lithium in isobutane. Polystyrene particles are continuously formed and discharged from the first reactor to the second reactor.
Butadiene is continuously fed to the second reactor and which continuously discharges to a third reactor (not shown).
Styrene is continuously fed to the third reactor.
The las-t reactor discharges to a settling column where the particles are separated from the reactor fluid . , . .

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by dropping -through the fresh up-flowiny isobutane. The overhead fluid from -the column is sent -to a purification sec-tion. The block copolymer slurry is discharged through a flash heater tube to a flash tank. Almost all the hydro~-carbon fluid is vaporized in the flash tube. The vapors from the flash tank are compressed, condensed and the con-densate is recycled to the wash column.
The b]ock polymer particles are discharged from the flash tank to a fluid bed dryer where the remainder of the hydrocarbon fluid is vaporized and separated. The dry thermo-plastic block copolymer is discharged from the fluid bed dryer to a pneumatic conveying system and thence packaged.
Example 3 The same process is used to manufacture ethylene-propylene-diene rubber. Propylene liquid is pumped through 3A and 13X molecular sieve in sequence. Propylene is the diluent for the process. Ethylene is passed through 3A and 13X molecular sieves and mixed in-line with the propylene.
Diene monomer, catalyst modifier and the aluminum alkyl catalyst component are also mixed in the propylene stream enroute to the reactor. The vanadium ca-talyst component is metered separately to the reactor.
The reactor is equipped for reflux cooling. Reflux cooling may be accomplished as described in Example 1 or with the use of a compressor to provide auto-refrigeration and propylene recycle. Concentrations of polymer particles is normally 25 to 35%. The reactor discharges continuously by level control to a settling column where the rubber parti-cles drop through the up-flowing fresh propylene. The overhead from the settling column may be partially recycled to the reactor to conserve catalyst and evergy and the ~.~'7~3~
remainder ls sent to a puriflcation unlt.
The slurry oE rubher particles ls discharged through a heated flash tube -to a flash -tanlc. The tempera-ture of the rubber particles is controlled to prevent stick-iness by the design and amount of heat supplied to the flash tube.
Essentially all of the propylene is vaporized in a flash tube, separated in the flash tank and compressed, condensed and the condensate is recycled to the settling column. The rubber particles are discharged to a fluid bed dryer which vaporizes and removes remaining hydrocarbon.
The rubber particles are discharged continuously from the fluid bed dryer and pneumatically conveyed to the baling and packaging line.
;~ Example 4 Cis-polybutadiene rubber is manufactured by the same process sutadiene, 30 wt.% in n-butane, is metered sequentially through 3A and 13~ molecular sieves and mixed in line to the reactor with catalytic amounts of water modifier, a Lewis base modifier and aluminum alkyl catalyst component. A cobalt catalyst component is metered separately to the reactor.
The reactor(s) is equipped for reflux cooling ; using either direct condensation of -the vaporized butane and butadiene or by an auto-refrigeration system. The cis polybutadiene rubber is a slurry in the diluent. The re-actor continuously discharges the 30 wt.~ slurry to the settling column where the rubber particles drop through up-flowing fresh n-butane. The diluent from the reactor thus is discharged from the top of the column. The fluid from ' .' " , ..

-the -top of the column may be partially recycled to conserve catalyst and energy ancl the remainder ls sent -to purification.
The slurry from -the bottom of the settl:ing column is discharged continuously through a flash tube heater where essentially all the diluent is vaporized to a Elash tank where the particles are separated. The vapor is compressed, condensed and recycled to the column. The rubber particles are discharged continuously to a fluid bed dryer where the remaining hydrocarbon is vaporized and removed. The dry-cis-polybutadiene particles ranging from 1/6" to 1/4" are discharged from the dryer and pneumatically conveyed to the baling and packaging line.
Example 5 Cis polyisoprene is manufactured by the same pro-cess. Isoprene, 30 wt.% in isobutane, is continuously metered sequentially through 3A and 13X molecular sieves and mixed in-line to the reactor(s) with aluminum alkyl catalyst com-ponent and a catalyst modifier. A titanium catalyst com-ponent is metered separately to the reactor.
The reactor(s) is equipped for reflux cooling ; using either direct condensation o~ the vaporized isobutane or an auto-refrigeration system. The cis-polyisoprene rub-ber is a slurry in the diluent. The reactor(s) continuously discharges the 30 wt. ~ slurry to the settling column where the rubber particles drop through the up-flowing fresh iso-butane. The diluent from the reactor thus is discharged f~om the top of the column~ This fluid from the top of the column may be partially recycled fro~ the top of the column to the reactor to conserve catalyst and energy and the re-mainder is sent to the purification system.

r~

. . , ~ .

, ~l ~2 7~3~3~
The slurry Erom -the bottom of the set-tl:ing column is discharged con-tinuously through -the flash heater tube where essentlally all the diluent is vaporlzed -to the Elash -tank.
Elashing temperature is controlled to prevent stickiness.
The vapor is compressed, condensed and recycled to the set-tling column. The rubber particles are discharged to the fluid bed dryer where the remainder oE the light hydrocarbons are vaporized and removed.
~ The dry, cis-polyisoprene rubber particles are dis-charged continuously from the fluid bed dryer and pneumati-cally conveyed to the baling and packaging line.
Example 6 Epichlorohydrin homo and copolymer with ethylene oxide is manufactured by the same process. Epichlorohydrin or epichlorohydrin and ethylene oxide, 30 wt.% in isobutane, are continuously metered sequentially through 3A and 13X
molecular sieves and mixed in-line to the reactor(s) with a catalytic quantity of water. An aluminum alkyl catalyst component is metered separately to the reactor(s).
The reactor(s) is equipped either for direct con-densing of vaporized isobutane or with an auto-refrigeration system. Epichlorin rubber is a slurry in the diluent. The . .
reactor(s~ continuously discharges a 30 wt.~ slurry to the settling column where the rubber particles drop through the up-flowing fresh isobutane. The diluent from the reactor is thus discharged from the top of the settling column. This fluid may be partially recycled to the reactor to conserve catalyst and energy and the remainder is sent to the puri-fication system.

- l 9 a ' '. ` ` '' ~'7~31~.~
The slurry Erom the bot-tom of -the se-ttling column is continuously clischarged -tllrough the Elash heater tube where essentially all -the dlluent is vaporized to the elash tank. Flashlng temperature was controlled -to preven-t stick-iness of the epichlorohydrin rubber particles. The vapor from the flash tank is compressed, condensed and recycled to the settling column. The rubber particles are discharged to -the fluid bed dryer where any remaining llght hydrocarbon is vaporized and removed.
The dry, epichlorohydrin rubber particles are con-tinuously discharged from the fluid bed dryer and pneumati-cally conveyed to the baling and packaging line.
Example 7 ~utyl rubber (97% isobutylene-3~ isoprene) is manufactured by the same process. Isobutylene-isoprene, 30 wt.% in methyl chloride, is continuously metered sequen-tially through 3A and 13X molecular sieved and ~ixed in line to the reactor(s) with catalytic quantities of water.
Aluminum alkyl chloride catalyst component is metered separ-ately to the reactor.
The reactor(s) are e~uipped with either direct condensation of vaporized methyl chloride or with an auto-refrigeration system. Butyl rubber is a slurry in methyl chloride. The reactor(s) continuously discharges the 30Wt~
slurry to the settling column where the particles drop through up-flowin~ fresh methyl chloride. The diluent from the re-actor is thus discharged from the top of the settling column.
This fluid may be partially recycled to conserve catalyst and energy and the remainder is sent to the purification system.

~ r - l~b -3~
The slurry from the bot-tom of the settling column is continuously d:ischarged through the flash heater where essentlally all the diluent and ligh-t hydrocarbons vaporize to the :Elash tank. Flashing temperature is controlled to prevent stickiness of the rubber particles. The vapor from the flash tank is compressed, condensed and recycled to the settling column. The butyl rubber particles are discharged to the fluid bed dryer where any remaining methyl chloride and light hydrocarbons are vaporised and removed.
The dry butyl rubber particles were discharged continuously and pneumatically conveyed to the baling and packaging line.
Example 8 Solution polymerized cis-polybutadiene is manu-factured by a slight modification of this process. suta-diene, 15 wt% in cis-butene-2, is continuously metered se-quentially through 3A and 13X molecular sieves and mixed in-line to the reactor(s) with catalytic amounts of water, a modifier and an aluminum alkyl catalyst component. A
cobalt catalyst component is metered separately to the re-actor(s).
The reactor(s) is equipped for either direct con-densation of cis-butene-2 and butadiene vapor or with an auto-refrigeration system.

- l 9 c ~.27~;3~3~

Cis-polybutadiene i5 a solution in cis-butene-2. The reactor(s) continuously discharge the 15% cis-polybutadiene soluti~n through the flash heater tube to the flash tank without the use of column 197. The cis-polybutadiene solution is almost instantaneously converted to particles conveyed in cis-butene-2 and butadiene vapor in the flash tube. The flash tank separates the vapor and cis-polybutadiene particles. The vapor is ccmpressed, condensed and sent to the purification system.
The ruhber particles discharged to the fluid becl dryer where any remaining light hydrocar~ons are vaporized and rem~ved. The dry cis-polybutadiene particles are discharged continuously from the dryer and pneumatically conveyed to the baling and packaging line.
EXample 9 Solution polymerized cis-polyisoprene is manufactured by a slight modification of this process. Isoprene, 15 Wt~ in cis-butene-2, is continuously metered sequentially through 3A and 13X molecular sieves and nuxed in-line to the reactor(s) with a modifier and an aluminum aLkyl catalyst component. A titanium catalyst component is metered separately to the reactor~s~.
The reactor(s) is equipped either f~r direct condensation of the ci~--butene-2 and isoprene vapor or with an auto-refrigelation system.
Cis-polyisoprene is a solution in cis-butene-2.
The reactor discharges continuously to an in-line muxer where it is mixed with a small amount of a catalyst co~?lexing agent and then to a hy ~ocyclone or centrifuge to separate the ccnplexed catalyst.
The clarified cis-polyisoprene solution is then flashed in the heated flash tube where it is essentially instantaneously converted to cis polysiopxene particles in cis-butene-2 vapor. m e flash temperature is contxolled to prevent stickiness. me gas and xubker particles are separated in the flash tank. The vapors are compressed, condensed and sent to the purification system.

The ru~ber particles from the flash tank are cont muously discharged to the fluid bed dryer where any remaining light hydrocaxbons ~ -20-~2~

are vaporized and removed. The cis-polyisoprene rubber particles are continuously discharyed from the dryer and pnuematically conveyed to the baling and packaging line.
It is to be understood that the process of this invention is not limited to the specific pieces of equipment described above~
For example, batch operation would be sequential rather than continual running of the reactors with the reactors charging from the feed streams and discharging through the column and flash tube.
~ccordingly, although the system described in detail above is most satisfactory and preferred, many variations in structure and method are possible, such as changes in vessels, valves and materials of construction describ~d ~E~-Because many varying and different embodinents may be made withinthe scope of the inventive concept herein taught, and because mcdifications may be made in accord3nce wit~ the descriptive requirements of the law, it should be understood that the details herein are to be interpreted as illustrative and not in a limiting sense.

', ' ' . ' ' '

Claims (66)

1. Apparatus for the manufacture of rubber from a variety of feeds, comprising:
feed means for selecting a subset of the variety of feeds and conveying said subset of the feeds;
reaction means for receiving said subset from the feed means and for reacting the feeds to produce a product in a mixture;
product separation means for receiving said product and separating said product from the other components of said mix-ture by settling;
evaporation means connected to said product separation means for separating said product from said other components;
compression means;
diluent purification means;
product drying means; and product finishing means, whereby many rubbers are produced by the same equipment.

2. The apparatus of claim 1, wherein said feed means includes purification columns having sieve means for purifying the subset of feeds, said sieve means including fine molecular sleves.

3. The apparatus of claim 2, wherein said sieves include 3A and 13X molecular sieves.

4. The apparatus of claim 1, wherein the feeds in-clude components for reacting in said reactor means to form said products which are particulate products in a suitable diluent, and further may include a Lewis base.

5. The apparatus of claim 4, wherein the Lewis base is taken from the class of ethers, tri-alkylamines or disul-fides for the production of said products of the classes of cis-polybutadiene, cis-polyisoprene, styrene-butadiene rubber, styrene-butadiene thermoplastic rubber and ethylene-propylene-diene rubber in particulate form.

6. The apparatus of claim 1, wherein the feed in cludes low boiling organic diluents, said evaporation means includes a heated flash pipe and a flash chamber, said pipe flashing said mixture containing said product to separate in said flash chamber said product from vaporized other components, said components being low boiling organic di-luents surrounding said product.

7. The apparatus of claim 6, wherein said reactor means includes at least one reactor, said separation means includes a settling column, and said reactor, settling column, and said flash chamber are coated with electroless nickel.

8. The apparatus of claim 6, wherein the temperature in said flash chamber is controlled in part by the boiling point of the diluent.

9. The apparatus of claim 8, wherein the diluents are selected from C3, C4, C5 hydrocaxbons and C1 chlorinated hydrocarbons, or mixtures of these, whereby direct particulation and separation of particles and diluent occur in said flash tube.

10. The apparatus of claim 1, wherein said subset of the feeds includes solvents taken from the class of cis-butene-2 and internally unsaturated, cis configuration C5 for the production of said products in the class of cis-polybutadiene, cis-polyisoprene, styrene-butadiene rubber, and styrene-butadiene thermoplastic rubber.

11. The apparatus of claim 1, wherein the feeds include a diluent and said product is a liquid polymer;
the said separation means comprises a decanter having means for decanting said liquid rubbers from said other components, and the said evaporation means comprises a film evaporator for removing the last residues of the diluent.

12. The apparatus of claim l, wherein said separation means includes a settling column and the feed includes a diluent and constituents and said separation means includes feed means for feeding fresh quantities of the diluent to said column substantially in the absence of water, whereby said particulate product is separated in the absence of water or steam.

13. The apparatus of claim 1, wherein said evaporation means includes a flash tube having means for flashing said product and a flash chamber to separate said product from said other components, said other components having low boiling point organic liquids, substantially in the absence of water and wherein said evaporation means further includes a fluid bed dryer having means for separating said product dry from said volatiles substantially in the absence of water.

14. A process for the manufacture of rubbers, compri-sing:
purifying a set of feed stocks having reaction components and diluents;
conveying the set of feed stocks to form a product;
separating the product from the remaining reaction compo-nents by settling;
separating the product from the diluent by vaporizing the diluent or solution from the product in the absence of water;
compressing the vaporized diluent or solution;
purifying the compressed diluent;
drying the products in a dryer; and finishing the product, whereby many rubbers are produced by the same equipment.

15. Apparatus for the manufacture of rubber from one or more of monomer and diluent and hydrogen and aluminum alkyl and other catalyst and modifier, comprising:

first feed means for purifying the diluent, including a first column packed with 3A molecular sieves and a second column packed with 13X molecular sieves;
second feed means for purifying the monomer, including a third column packed with 3A molecular sieves and a fourth column packed with 13X molecular sieves;
third feed means for purifying a second monomer, in-cluding a fifth column packed with 3A molecular sieves and a sixth column packed with 13X molecular sieves;
fourth feed means for purifying the hydrogen, including a seventh column packed with 3A molecular sieves;
fifth feed means for metering the aluminum alkyl cata-lyst;
sixth feed means for metering the modifier;
seventh feed means for metering the catalyst component;
a reactor system connected to all of said feed means and having means for reacting the feeds to produce a slurry of product particles and low boiling organic liquids;
a separating column connected to the outlet of said reactor system, said separating column having separation means for introducing a clean low boiling organic liquid at the bottom of said separating column to separate said particles from said slurry or solution of product and set-tling means for permitting said particles of product to settle in said clean low boiling organic liquid;
a flash tube connected to the bottom of said separating column for heating and completely vaporizing said low boiling organic liquid and using the vapors to pneumatically convey the product particles;

a flash tank connected to said flash tube having means for permitting said product to be separated from the vapor substantially in the absence of water;
compressors connected to the vapor outlet of said flash tank and having first means for liquifying vapor from said flash tank and conveying said condensed vapor to said separa-ting column as said clean, low boiling organic liquid and second means for conveying a portion of said vapor prior to liquification to the bottom of said separating column to act as supplemental conveying agent for said product particles through said flash tube and into said flash tank; and a fluid bed dryer having means for separating said product dry from the remainder of said low boiling organic liquid, substantially in the absence of water.

16. A process for the manufacture of rubber, comprising:
A. metering and providing feed stock;
B. reacting the feed stock to produce an effluent of a rubber product and other components;
C. separating the rubber product and other components by settling;
D. evaporating the effluent of Step C to separate the rubber product from other components.
E. compressing the evaporated effluent;
F. purifying the compressed effluent;
G. drying the separated rubber product; and H. finishing the dried product.

17. The process of claim 16, wherein the feed stock includes at least one diluent and a Lewis base; and the effluent of Step B includes particulate rubber product and the diluent.

18. The process of claim 17, wherein the Lewis base is taken from the class of ethers, tri-alkylamines or disulfides and the particulate rubber product is from the class of cis-polybutadiene, cis-polyisoprene, styrene-butadiene rubber, styrene-butadiene thermoplastic rubber, ethylene-propylene-diene rubber, thermoplastic ethylene-propylene rubber, butyl rubber and epichlorohydrin-ethylene oxide rubber.

19. The process of claim 17, wherein the feed stock diluents are selected from C3, C4, and C5 hydrocarbons and C1 chlorinated hydrocarbons or a mixture of these.

20. The process of claim 17, wherein the product is taken from a class of liquid polymers.

21. The process of claim 20, wherein the liquid polymers are from the class of cis-polybutadiene, cis-polyisoprene, styrene-butadiene rubber and ethylene-propylene-diene rubber.

22. The process of claim 16, wherein there is included the step of purifying the feedstock by 3A and 13X molecular sieves prior to Step B.

23. A process for the manufacture of rubber, comprising:
A. metering and providing a feedstock;
B. reacting the feedstock to produce an effluent of a particulate rubber product and other components;

C. separating the particulate rubber product from the other components substantially in the absence of water; and D. evaporating the effluent of Step C to separate the particulate rubber product from the other components substan-tially in the absence of water.
E. compressing the evaporated effluent F. purifying the compressed effluent;
G. drying the separated rubber product; and H. finishing the dried product.

24. Apparatus for the manufacture of rubber from a variety of feeds, comprising:
feed means for selecting a subset of the variety of feeds and conveying said subset of the feeds;
reaction means for receiving said subset from the feed means and for reacting the feeds to produce a product mixture;
product separation means for receiving said product mix-ture and separating said product from the other components of said mixture by density separation, evaporation means connected to said product separation means for separating said product from said other components:
compression means;
diluent purification means;
product drying means; and product finishing means, whereby many rubbers are produced by the same equipment.

25. The apparatus of claim 24, wherein said product separation means includes a decanter and an evaporator, said evaporator connected to one of the outlets of said decanter;
whereby liquid rubbers are produced.

26. Apparatus for the manufacture of rubber from a variety of feeds, comprising:
feed means for selecting a subset of the variety of feeds including catalyst and conveying said subset of the feeds;
reaction means for receiving said subset from the feed means and for reacting the feeds to produce a product solu-tion;
product preparation means for receiving said product solu-tion and separating the catalyst from said product solution by density separation;
product separation means for receiving said product solu-tion from said product preparation means and separating said product from the other components of said solution, compression means;
diluent purification means;
product drying means; and product finishing means, whereby many rubbers are produced by the same equipment.

27. The apparatus of claim 26, wherein said product preparation means includes:
a mixer, means for introducing a catalyst complexing agent into said mixer;
separator means for separating denser catalyst complex from said product effluent of said mixer; and said product separation means includes:
vaporization means connected to said separator means for separating said product from said other components, and drying means for removing residual volatiles of said other components from said product.

28. A process for the manufacture of rubbers, compri-sing:
A. purifying a set of feed stocks having reaction and catalyst components and solvents;
B. reacting the set of feed stocks to form a rubber in solution;
C. separating the rubber solution from the catalyst by density separation;
D. separating the rubber from the solvent of the rubber solution by vaporizing the solvent to produce rubber particles in the absence of water;
E. compressing the vaporized solvent;
F. purifying the compressed solvent;
G. drying the rubber particles.
H. Finishing the dried rubber particles.

29. The process of claim 28, wherein Step C includes the steps of:
mixing the rubber solution in a mixer with a catalyst complexing agent; and separating denser catalyst complex from the rubber solu-tion.

30. A process for the manufacture of liquid rubbers, comprising:
A. purifying a set of feed stocks having reaction compo-nents and diluents;
B. reacting the set of feed stocks to form a liquid rubber mixture;
C. separating the liquid rubber from the other components of the mixture by density separation; and D. removing residual volatiles of the mixture by evapora-tion to produce rubber particles, E. compressing the vaporized solvent;
F. purifying the compressed solvent;
G. drying the rubber particles; and H. finishing the dried rubber particles.

31. The process of claim 30, wherein:
Step A includes the step of selecting a diluent from a class of diluents which is not a solvent of the liquid rubber;
Step C includes the step of decanting the liquid rubber and diluent in a decanter; and Step D includes the step of evaporating the decanter effluent in a film evaporator.

- 31a -

32. The apparatus of claim 1, 2 or 4, wherein the rubber that can be produced is a member selected from the group consisting of styrene-butadiene rubber, ethylene oxide-epichlorohydrin rubber, styrene-butadiene thermoplastic rubber cis-polybutadiene, cis-polyisoprene, ethylene propylene diene rubber, thermoplastic ethylene-propylene rubber and butyl rubber.

33. The apparatus of claim 11, wherein the liquid polymer is a member selected from the group consisting of cis-polybutadiene, cis-polyisoprene, styrene-butadiene rubber, and ethylene-propylene-diene rubber.

34. The process of claim 14, wherein the rubber is a member selected from the group consisting of styrene-butadiene rubber, styrene-butadiene thermoplastic rubber, cis-polybutadiene, epichlorohydrin-ethylene oxide rubber, cis-polyisoprene, ethylene-propylene-diene rubber, thermo-plastic ethylene-propylene rubber and butyl rubber.

35. An apparatus for the manufacture of rubber utilizing monomer and diluents and catalysts, comprising:
A. a reactor system;
B. means for feeding substantially only a set of the monomers and diluents taken from the following table and cata-lysts to said reactor system-- with a diluent selected from C3, C4, C5 hydrocarbons and C1 chlorinated hydrocarbons or a mixture of these, said means for feeding including means for purifying the monomer;
C. said reactor system having means for reacting the set of monomers, diluents and catalysts in said reactor system to form a particulate rubber product set out in said table;
D. a purification system having fresh diluent and means for receiving said product in said purification system;
E. means for purifying said product in said purification system for the remaining reaction components by settling said product in the fresh diluent;
F. means for separating said product from the diluent by flash evaporating the diluent from said product in the absence of water and steam and additives which facilitate the vapori-zing;
G. means for compressing the vaporized diluent, H. a dryer having means for drying said product; and whereby the group consisting of ethylene-propylene-diene rubber, butyl rubber and epichlorohydrin rubber are all produced by substantially the same apparatus, and I. means for finishing the product.

36. The apparatus of claim 35, wherein there is included a Lewis base; and the effluent from said means for reacting -- 33a -includes particulate rubber product and the diluent.

37. The apparatus of claim 36, wherein the Lewis base is taken from the class of ethers, tri-alkylamines or disulfides.

38. The apparatus of claim 36, where there is included means for purifying the monomer and diluent in route to said reactor system, said means for purifying including 3A and 13X
molecular sieves in series to remove traces of impurities in front of said reactor system.

39. The apparatus of claim 35, wherein said means for separating includes a flash chamber for separating said particulate rubber product from the surrounding vaporized low boiling hydrocarbon diluents.

40. The apparatus of claim 35, wherein said reactor system includes at least one reactor, said means for purifying includes a settling column, said means for separating includes a flash chamber, and said reactor, settling column and said flash chamber are electropolished or coated with electroless nickel.

41. The apparatus of claim 40, wherein said means for separating includes a heated flash tube having means for supplying heat to said rubber particles, said heated flash tube being located between said settling column and said flash chamber.

42. The apparatus of claim 41, wherein said means for separating includes means for separation in said flash chamber to separate said rubber particles from the vaporized diluent in the absence of water or steam and said means for separating further includes a fluid bed dryer having second means for evaporation of diluent in the absence of water or steam.

43. The apparatus of claim 42, wherein said means for separating includes means for controlling the temperature of said rubber in said flash chamber by the selection of the diluent(s).

44. The apparatus of claim 42, wherein means for purifying includes a settling column and said product includes diluent(s), and said particulate rubber product, including the diluents, are purified by means for settling through fresh quantities of the diluent, whereby said product is purified in the absence of steam or water.

45. The apparatus of claim 35, wherein the diluent is taken from the following table:

46. An apparatus for the manufacture of rubber using monomer, diluent and catalyst, comprising:
A. a reaction system;
B. means for feeding the monomer, diluent and catalyst to said reaction system, said means for feeding including means for purifying the monomer;
C. said reactor system including means for reacting the monomer, diluent and catalyst to produce an effluent of a rubber product and other components;

D. means for receiving said rubber product and other components;
E. a purifying system including means for purifying said rubber product from the other components by settling said rubber product into fresh diluent, substantially in the absence of additives which facilitate the settling;
F. means for evaporating the effluent from said purifying means to separate said rubber product from other components substantially in the absence of water or additives which faci-litate the evaporating.
G. means for compressing the evaporated effluent;
H. means for purifying the compressed effluent;
I. means for drying the rubber product; and J. means for finishing the rubber product.

47. The apparatus of claim 46, wherein the feed stock includes diluents selected from C3, C4, and C5 hydrocarbons and C1 chlorinated hydrocarbons or a mixture of these, whereby said product is particulate rubber product produced in said reactor system without significant precipitation.

48. The process of claim 47, wherein the diluents are chosen from propane, propylene, butane, isobutane, cis-butene-2, trans-butene-2, pentanes, internally unsaturated C5 olefins, and methyl chloride.

49. An apparatus for the manufacture of rubber from a feedstock of monomer and diluent and catalyst;
A. means for purifying the monomer and diluent;
B. a reactor system having means for conveying the puri-fied feedstock to said reactor system;

C. said reactor system having means for reacting the monomer in said reactor system to produce an effluent of a rubber product and other components;
D. means for purifying said rubber product by fresh diluent;
E. means for separating the effluent of said means for purifying to separate dry rubber product in low boiling hydro-carbon liquids substantially in the absence of water or steam or additives which facilitate the settlement.
F. means for compressing the evaporated effluent;
G. means for purifying the compressed effluent;
H. means for drying the rubber product; and I. means for finishing the rubber product.

50. An apparatus for the manufacture of rubber, taken from the following table and catalyst-- comprising:
A. means for metering and feeding monomers and diluents;
B. a reactor system having means for feeding substantial-ly only the monomers and diluents to said reactor system, said means for feeding including means for purifying the monomer and said reactor system including means for reacting the set of monomers, diluents and catalysts in said reactor system to form a particulate rubber product set out in the above table;
C. a purification system having means for receiving said product and means for purifying said product in said purifica-tion system from remaining components by settling said product in fresh diluent, D. means for separating said product from the diluent by flash evaporating the diluent from said product in the absence of water and steam and additives which facilitate the vapori-zing; and E. means for compressing the evaporated diluent;
F. means for purifying the diluent;
G. means for finish drying the product in a dryer, H. means for finishing the product, whereby the group consisting of ethylene-propylene-diene rubber, butyl rubber and epichlorohydrin rubber are all produced by substantially the same apparatus.

51. A process for the manufacture of rubber, comprising:
A. feeding substantially only a set of monomers and diluents taken from the following table and catalysts to a reaction system with a diluent selected from C3, C4 and C5 hydrocarbons and C1 chlorinated hydrocarbons or a mixture of these, said feeding including purifying the monomer;
B. reacting the set of monomers, diluents and catalysts in the reactor system to form a particulate rubber product set out in said table;
C. receiving the product in a purification system D. purifying the product in the purification system from the remaining reaction components by settling the product in fresh diluent;
E. separating the product from the diluent by flash evaporating the diluent from the product in the absence of water and steam and additives which facilitate the vaporizing;
F. compressing the evaporated diluent:
G. purifying the diluent;
H. drying the product in a dryer;
I. finishing the product;
where by the group consisting of ethylene-propylene-diene rubber, butyl rubber and epichlorohydrin rubber are all produced by substantially the same equipment.

- 38a -

52. The process of claim 51, wherein there is included a Lewis base; and the effuent of Step a includes particulate rubber product and the diluent.

53. The process of claim 52, wherein the Lewis base is taken from the class of ethers, tri-alkylamines or disulfides.

54. The process of claim 51, where there is included the step of purifying the monomer and diluent in route to the reactor system by 3A and 13X molecular sieves in series to remove traces of impurities prior to Step B.

55. The process of claim 51, wherein Step E occurs in a flash chamber for separating the particulate rubber product from the surrounding vaporized low boiling hydrocarbon diluents.

56. The process of claim 51, wherein said Step E occurs in at least one reactor, said Steps C and D occur in a settling column, said Step E occurs in a flash chamber, and reactor, settling column and flash chamber are electropolished or coated with electroless nickel.

57. The process of claim 56, wherein Step E includes supplying heat to the rubber particles in a heated flash tube, the heated flash tube being located between the settling column and the flash chamber.

58. The process of claim 57, wherein Step E includes separation in the flash chamber to separate the rubber particles from the vaporized diluent in the absence of water or steam and Step E further includes further evaporation of diluent on a fluid bed dryer in the absence of water or steam.

59. The process of claim 56, wherein Step E includes the step of controlling the temperature of the rubber in the flash chamber in a part by the selection of diluent(s).

60. The process of claim 51, wherein the purification system includes a settling column and the product includes diluent(s), and the particulate rubber product, including the diluents, are purified by settling through fresh quantities of diluent, whereby the product is purified in the absence of steam or water.

61. The process for the manufacture of rubber of claim 51 wherein the diluent is taken from the following table:

62. A process for the manufacture of rubber, comprising:

A. feeding monomer, diluent and catalyst to a reaction system, said feeding including purifying the monomer;
B. reacting the monomer, diluent and catalyst to produce an effluent of a rubber product and other components;
C. receiving the rubber product and other components in a purifying system;
D. purifying the rubber product from the other components by settling the product into fresh diluent, substantially in the absence of additives which facilitate the settling;
E. evaporating the effluent of Step D to separate the rubber product from the other components substantially in the absence of water or additives which facilitate the evapora-ting.
F. compressing the evaporated effluent;
G. purifying the compressed effluent;
H. drying the rubber product; and I. finishing the rubber product.

63. The process of claim 62, wherein the feed stock includes diluents selected from C3, C4, and C5 hydrocarbons and C1 chlorinated hydrocarbons or a mixture of these, whereby particulate rubber product is produced in the reactor system without significant precipitation.

64. The process of claim 63, wherein the diluents are chosen from propane, propylene, butane, isobutane, cis-butene-2, trans-butene-2, pentanes, internally unsaturated C5 olefins, and methyl chloride.

65. A process for the manufacture of rubber, comprising:
A. providing a feedstock of monomer and diluent and cata-lyst;
B. purifying the monomer and diluent;
C. conveying the purified feedstock to a reactor system;
D. reacting the monomer in the reactor system to produce an effluent of a rubber product and other components;
E. purifying the rubber product by fresh diluent;

F. separating the effluent of Step E to separate rubber product in low boiling hydrocarbon liquids substantially in the absence of water or steam or additives which facilitate the settlement.
G. compressing the effluent;
H. purifying the compressed effluent;
I. drying the rubber product; and J. finishing the rubber product.

66. A process for the manufacture of rubber, comprising:
A. feeding substantially only a set of monomers and diluents taken from the following table and catalysts to a reaction system said feeding including purifying the monomer;
B. reacting the set of monomers, diluents and catalysts in the reactor system to form a particulate rubber product set out in said table;
C. receiving the product in a purification system;
D. purifying the product in the purification system from the remaining reaction components by settling the product in fresh diluent E. separating the product from the diluent by flash evaporating the diluent from the product in the absence of water and steam and additives which facilitate the vaporizing;
F. compressing the evaporated diluent, G. purifying the compressed diluent;

H. drying the product in a dryer and I. finishing the product;
whereby the group consisting of ethylene-propylene-diene rubber, butyl rubber and epichlorohydrin rubbers are all produced by substantially the same equipment.