Butyl terpolymer

Polybutene and polyisobutylene - are the most frequently used plasticizers. Paraffinic, naphthenic, and aromatic process oils are also used. Esters of fatly acids and phosphates are also used but are less common.  

---

In addition to taking the butyl rubber project from conception to commercialization on a large scale. Bob Thomas worked with Baldwin in development of Chlorobutyl rubber (U.S. Pat. 2,926,718) and with Minkler on the development of butyl terpolymers. 

There are now ten facilities, worldwide, producing butyl rubbers (Table 1) with an aggregate nameplate capacity exceeding 500 x 10 t. Esso, Exxon and the two Polysar plants include halobutyl rubbers in their product lines. Polysar Ltd is the only producer of crosslinked butyl terpolymers. 

The manufacturing process for butyl terpolymers involves only minor changes to the procedure and equipment used for unmodified butyl rubbers, and, being continuous, generates products with a high level of uniformity. 

Numerous recipes have been pubUshed, primarily ia the patent Hterature, that describe the preparation of acrylate and methacrylate homopolymer and copolymer dispersions (107,108). A typical process for the preparation of a 50% methyl methacrylate, 49% butyl acrylate, and 1% methacrylic acid terpolymer as an approximately 45% dispersion ia water begias with the foUowiag charges ... 

Most elastomers can be made iato either opea-ceUed or closed-ceUed materials. Natural mbber, SBR, nitrile mbber, polychloroprene, chlorosulfonated polyethylene, ethylene—propylene terpolymers, butyl mbbers, and polyacrylates have been successfuUy used (4,111,112). 

Tires, natural mbber tubes, and butyl tubes are the main sources of scrap and reclaim (see Elastomers, synthetic-polyisoprene). Specialty reclaim materials are made from scrap siUcone, chloroprene (CR), nitrile— butadiene (NBR), and ethylene—propjlene—diene—terpolymer (EPDM) mbber scraps (see... 

Prior to butyl mbber, the known natural and synthetic elastomers had reactive sites at every monomer unit. Unlike natural mbber, polychloroprene, and polybutadiene, butyl mbber had widely spaced olefin sites with aHyUc hydrogens. This led to the principle of limited functionahty synthetic elastomers that was later appHed to other synthetic elastomers, eg, chlorosulfonated polyethylene, siUcone mbber, and ethylene—propylene terpolymers. 

A partially cross-linked, isobutylene—isoprene—divinylbenzene terpolymer containing some unreacted substituted vinylbenzene appendages is commercially available from Polysar Division, Bayer AG. Because of the residual reactive functionality, it can be cross-linked by peroxides that degrade conventional butyl mbbets. It is employed primarily in the manufacture of sealant tapes and caulking compounds (31). 

Grades of polyisobutylene, butyl mbber, halogenated butyl mbber, and partially cross-linked isobutylene—isopiene—divinylbenzene terpolymer have been developed to meet specific processing and property needs. Recently, two new polyisobutylene-based elastomers have been developed. One is now available commercially as Exxon SB Butyl Polymers (32) and the other is under market development as Exxon bromo XP-50. 

Whilst polyisobutene is a non-rubbery polymer exhibiting high cold flow (see Section 11.3), the copolymer containing about 2% isoprene can be vulcanised with a powerful accelerated sulphur system to give moderately rubbery polymers. The copolymers were first developed in 1940 by Esso and are known as butyl rubbers and designated as HR. As they are almost saturated they have many properties broadly similar to the EPDM terpolymers. They do, however, have two properties that should be particularly noted ... 

New copolymers based on a copolymerization of isobutylene and p-methyl-styrene with improved heat resistance have been reported [64]. Once copolymerization was accomplished, the polymer was selectively brominated in the p-methyl position to yield a terpolymer called EXXPO. In contrast to butyl and halobutyl, the new terpolymer has no unsaturation in the backbone and therefore shows enhanced thermal stability and resistance to oxidation. Useful solvent-based adhesives can be formulated using the new terpolymer in combination with block copolymers [65]. The hydrocarbon nature of the new terpolymer results in excellent compatibility with hydrocarbon resins and oils. 

Standard butyl rubber, which is a copolymer of isobutylene with about 2% of isoprene vulcanises in the same manner as natural rubber but, as it only contains a small proportion of polyisoprene, the cross-link percentage is much reduced. It is therefore not possible to make ebonite from a butyl rubber. The same vulcanisation chemistry, with some modifications, applies to ethylene-propylene terpolymers and brominated butyl rubber. 

The most prevalent approach to achieve long-lasting and nonstaining ozone protection of rubber compounds is to use an inherently ozone-resistant, saturated backbone polymer in blends with a diene rubber. The ozone-resistant polymer must be used in sufficient concentration (minimum 25 phr) and must also be sufficiently dispersed to form domains that effectively block the continuous propagation of an ozone-initiated crack through the diene rubber phase within the compound. Elastomers such as ethylene-propylene-diene terpolymers, halogenated butyl mbbers, or brominated isobutylene-co-para-methylstyrene elastomers have been proposed in combination with NR and/or butadiene rubber. 

Acrylamide copolymers designed to reduce undesired amide group hydrolysis, increase thermal stability, and improve solubility in saline media have been synthesized and studied for EOR applications. These polymers still tend to be shear sensitive. Acrylamide comonomers that have been used include 2-acrylamido-2-methylpropane sulfonate, abbreviated AMPS, (1,321-324), 2-sulfo-ethylmethacrylate (325,326), diacetone acrylamide (324, 326), and vinylpyrrolidinone (327,328). Acrylamide terpolymers include those with sodium acrylate and acrylamido-N-dodecyl-N-butyl sulfonate (329), with AMPS and N,N-dimethylacrylamide (330), with AMPS and N-vinylpyrrolidinone (331), and with sodium acrylate and sodium methacrylate (332). While most copolymers tested have been random copolymers, block copolymers of acrylamide and AMPS also have utility in this application (333). 

E-BA-GMA (63 31 6) (ethylene-butyl acrylate-glycidyl methacrylate terpolymer) Elvaloy PTW DuPont... 

Figure 14.9 Effect of various impact modifiers (25wt%) on the notched Izod impact strength of recycled PET (as moulded and annealed at 150°C for 16 h) E-GMA, glycidyl-methacrylate-functionalized ethylene copolymer E-EA-GMA, ethylene-ethyl acrylate-glycidyl methacrylate (72/20/8) terpolymer E-EA, ethylene-ethyl acrylate EPR, ethylene propylene rubber MA-GPR, maleic anhydride grafted ethylene propylene rubber MBS, poly(methyl methacrylate)-g-poly(butadiene/styrene) BuA-C/S, poly(butyl acrylate-g-poly(methyl methacrylate) core/shell rubber. Data taken from Akkapeddi etal. [26]...

Several polymers based on 1,3-dienes are used as elastomers. These include styrene-1,3-butadiene (SBR), styrene-1,3-butadiene terpolymer with an unsaturated carboxylic acid (carboxylated SBR), acrylonitrile-1,3-butadiene (NBR or nitrile rubber) (Secs. 6-8a, 6-8e), isobutylene-isoprene (butyl rubber) (Sec. 5-2i-l), and block copolymers of isoprene or... 

Preparation of a Styrene/Butyl Acrylate/Methacrylic Acid Terpolymer Dispersion (Influence of Emulsifier)... 

Several high-performance or engineering polymers, such as the polyfluo-rocarbons, acetals, ABS, nylons, polyurethanes (PUs), silicones, and phos-phazenes, have been described in previous chapters. Several elastomers, such as butyl rubber, EPDM (elastomeric terpolymer from ethylene, propylene, and a nonconjugated diene), and Neoprene, which play a vital role in engineering, and a host of classic thermosets should also be considered high-performance polymers. The properties of other high-performance polymers are described in this chapter. 

Table 1 shows an example of the partial operating instructions and log for the preparation of a terpolymer of vinyl acetate, butyl acrylate, and vinyl neodecanoate. The details of these instructions will, of course, have to be individualized for specific situations. 

Copolymers of acrylonitrile and methyl acrylate and terpolymers of acrylonitrile, styrene, and methyl methacrylate are used as bamer polymers. Acrylonitrile copolymers and multipolymers containing butyl acrylate, ethyl aciylate, 2-ethylhexyl acrylate, hydroxyethyl acrylate, methyl methaciylate. vinyl acetate, vinyl ethers, and vinylidene chlonde are also used in bamer films, laminates, and coatings. Environmentally degradable polymers useful in packaging are prepared from polymerization of acrylonitrile with styrene and methyl vinyl ketone. 

The first free radical initiated copolymerization was described by Brubakerl) in a patent. A variety of peroxides and hydroperoxides, as well as, 02, were used as initiators. Olefins that were copolymerized with CO included ethylene, propylene, butadiene, CH2=CHX (X—Cl, OAc, CN) and tetrafluoroethylene. A similar procedure was also used to form terpolymers which incorporated CO, C2H4 and a second olefin such as propylene, isobutylene, butadiene, vinyl acetate, tetrafluoroethylene and diethyl maleate. In a subsequent paper, Brubaker 2), Coffman and Hoehn described in detail their procedure for the free radical initiated copolymerization of CO and C2H4. Di(tert-butyl)peroxide was the typical initiator. Combined gas pressures of up to 103 MPa (= 15,000 psi) and reaction temperatures of 120—165 °C were employed. Copolymers of molecular weight up to 8000 were obtained. The percentage of CO present in the C2H4—CO copolymer was dependent on several factors which included reaction temperature, pressure and composition of reaction mixture. Close to 50 mol % incorporation of CO in the copolymer may be achieved by using a monomer mixture that is >70 mol% CO. Other related procedures for the free radical... 

When evaluated by LOI, the system with zeolites has higher LOI than that without it. For example, compared with PP-APP-PER, which has an LOI of 30%, the LOI of PP-APP-PER system with zeolite 13X increases to 45%, an increase of 50%. Also the LOI of LRAM3.5 (ethylene-butyl acrylate-maleic anhydride terpolymer)-APP-PER system with 4A increases to 39%, relative to 29% for LRAM3.5-APP-PER system. All systems with zeolites obtained the UL-94V-0 grade. 

Block terpolymers consisting of butyl acrylate with either methylmethacrylate or methyl acrylate have been prepared where the end segments are at least 10,000 daltons and the center segment is at least 60,000 daltons. These materials were coated onto a polycarbonate surface and used to prepare an optical film and an optically clear pressure-sensitive adhesive layer that resists bubble formation when adhered to an outgassing substrate. 

Random terpolymers consisting of ethyl, butyl, and behenyl acrylate were prepared by the author [3] and used as heat-activatable adhesives. Randon terpolymers consisting of iso-octyl/acrylic acid/styrene macromonomer, 92/4/ 4 mol%, respectively, were prepared by Joseph [4] and used as a reinforced pressure sensitive adhesive. 

Linear and star diblock polymers consisting of methyl and n-butyl acrylates were prepared by Paul [5] and used as high performance, low viscosity hot-melt adhesives. A single star block terpolymer containing 2-ethyIhexyl acrylate was also prepared. 

Mercapto-terminated block copolymers and block terpolymers prepared by Tsuji [4] such as poly(acrylonitrile-b-butyl acrylate) and poly(acrylonitrile-b-butyl acrylate-b-ethyl acrylate), respectively, used the RAFT chain transfer agent cumyl dithiobenzoate. The block copolymer had a M of48,600 daltons. 

In contrast to the claims of the literature, vinyl ferrocene (available commercially) was found to be a very reactive monomer in the terpolymer system butyl acrylate/styrene/methacryllc acid. It was further found, again in contrast to the claims in the literature, that vinyl ferrocene could be emulsion polymerized via organic peroxide Redox catalysis. 

---