Styrene-butadiene-caprolactone

A polyblend of superior impact strength has been claimed by Phillips Petroleum (44) and is obtained by blending SAN with a styrene/butadiene/caprolactone terblock polymer. Impact PVC is manufactured by blending the homopolymer with an elastomeric compound such as ABS, MBS, or aery lonitri le/raethacry late/ butadiene/styrene (AMBS). 

A new process, which Involves the conversion of polymeric oxyl-llthlum to oxyl-aluminum chain end as modified ring-opening site for lactones, has proven to be very effective In eliminating trans-esterlflcatlons. Therefore, uniform block polymers containing styrene, butadiene, and e-caprolactone can be prepared with well defined structure ... 

As to Its other characteristics, styrene-butadlene-caprolactone (S-B-CL) trlblock terpolymer with high butadiene content behaves much like a thermoplastic elastomer, with raw tensile strength equal to and ozone resistance better than S-B-S type copolymer (3). The Impact-resistant resin by blending 25 parts of S-B-CL trlblock with 75 parts of styrene/acrylonltrlle (SAN) copolymer resembles ABS type material In such properties as tensile strength, flexural modulus, oil resistance, and transparency (4). 

The development of PEST/SBS blends parallels that of PA/SBS ones. First, blends of PBT, ABS, and SEBS were disclosed [Gergen and Davison, 1978]. Four years later the reactive compatibi-lization was discovered — PBT was blended with SEBS and SMA [Durbin et al., 1983]. By the end of 1970 s, multicomponent blends comprising, PBT, PET, PC, and either SEBS, (SB), butadiene-caprolactone-styrene, or butadi-ene-caprolactone block copolymer, were developed [Wambach and Dieck, 1980]. Reactive compati-bilization of PEST/SEBS by addition of MA was disclosed in 1984. The method was general, applicable to polyamides as well as to polyesters [Shiraishi and Goto, 1986]. 

Besides melt intercalation, described above, in situ intercalative polymerization of E-caprolactone (e-CL) has also been used [231] to prepare polycaprolactone (PCL)-based nanocomposites. The in situ intercalative polymerization, or monomer exfoliation, method was pioneered by Toyota Motor Company to create nylon-6/clay nanocomposites. The method involves in-reactor processing of e-CL and MMT, which has been ion-exchanged with the hydrochloride salt of aminolauric acid (12-aminodecanoic acid). Nanocomposite materials from polymers such as polystyrene, polyacrylates or methacrylates, styrene-butadiene rubber, polyester, polyurethane, and epoxy are amenable to the monomer approach. 

Schematic figures of the shape memory mechanism of the styrene-butadiene-styrene (SBS) triblock copolymer/poly(e-caprolactone) (PCL) blend in (a)-(d). (Adapted from Zhang, H., Wang, H., Zhong, W, and Du, Q. 2009. A novel type of shape memory polymer blend and the shape memory mechanism. Polymer 50 1596-1601. Copyright Elsevier Ltd. Reproduced with permission.)...

This assembly chemistry is only limited by the preparation of an appropriate amphiphilic or hydrophobic diblock copolymer. With the structure and chemical composition of the resultant nanoparticles readily tunable using a wide range of block copolymers that are synthetically available. A broad range of polymers have been utilized as the core hydrophobic domain of shell-crosslinked nanoparticles and include styrene, isoprene, butadiene, caprolactone, poly (ethylene oxide), acrylates, methacrylate and acrylamides. Monomers that have been used to prepare the hydrophilic water-soluble domain include, among others, poly(ethylene glycol), acrylic acid, 4-vinylpyridine, (meth)acrylic acid, 2-dimethylaminoethyl methacrylate and Wisopropylacrylamide. 

Diblock copolymers made of hydrogenated PBu and PA6 units (HPBU-PA6) have been s)mthesized in a similar manner (but hydrogenating the hydroxyl-terminated PBu) and used as compatibilizers in low-density poly(ethylene)/PA6 blends (PE/PAfi). " The diblock copolymer exhibited a very relevant interfacial activity, with a reduction of particle size and an improvement of the interfacial adhesion between the incompatible phases. Also hydroxyl-terminated styrene-butadiene rubber (SBR) or poly(E-caprolactone), after reaction with diisocyanates, were anionically copolymerized with CL in order to get block copolymers with improved mechanical properties. ... 

In the last twenty years, many polymers have been used to make polymer nanocomposites. Thermoplastic polymers include nylon, polyaniline (PANI), " poly(s-caprolactone), polycarbonate (PC), polyether ether ketone (PEEK), polyethylene (PE), poly(ethyl acrylate) (PEA), polyisoprene (PI), polylactide (PLA), poly(methyl methacrylate) (PMMA), " polypropylene (PP), polypyrrole (PPy)," polystyrene (ps)/ i i7,27,30,49-64 poiy inyl acetate) (PVAc), poly(vinyl alcohol) (PVA), poly(vinyl chloride) (PVC) and thermoplastic polyurethane (TPU), and thermosets include Bakelite, butadiene rubber, epoxy,polydimethylsiloxane (PDMS), polyurethane (PU), styrene-butadiene rubber (SBR) and unsaturated polyester resin. 

The triblock copolymer styrene-butadiene-c-caprolactone, the last being the crystallizable block, serves as example of a weakly segregated system.(67) Although both the overall crystallization and spherulite growth rates are reduced relative to the crystallizing homopolymer, the temperature ranges for isothermal crystallization are approximately the same for the copolymer and homopolymer. Consequently, the Avrami exponent is only slightly reduced from that of the parent homopolymer. 

Despite the drawbacks of this method, it has been used to prepare a tremendous number of polypeptide hybrid block copolymers (Table 1), and when carefully executed provides reasonably well-defined samples. Synthetic polymer domains have been prepared by addition polymerization of conventional vinyl monomers, such as styrene and butadiene, as well as by ringopening polymerization in the cases of ethylene oxide and e-caprolactone. The generality of this approach allows NCA polymerization off of virtually any primary amine functionality, which was exploited in the preparation of star block copolymers by polymerization of sarcosine NCA from an amine-terminated trimethyleneimine dendritic core [37]. In most examples, the polypeptide domain was based on derivatives of either lysine or glutamate, since these form a-helical polypeptides with good solubility characteristics. These residues are also desirable since, when deprotected, they give polypep-... 

Butadiene (B) sionomer vas flashed at 46 C from Its dimer and Inhibitor, then condensed by passing through activated alumina Into the container at -15 C under N2 pressure. Styrene (S), was either dried through activated alumina, or refluxed over CaH2 then vacuum distilled. e-Caprolactone (CL) was distilled from CaR2 at reduced pressure. Ethylene oxide (EO) was purchased from Eastman Chemical Co., diluted in dried cyclohexane before use and used without further purification. n-Butyllithlum (n-BuLi) In heptane was obtained from Alfa Products and dlethylalumlnum chloride (DEAC) was from Texas Alkyls. They were diluted In purified cyclohexane before... 

Tg and Tm Measurement. Glass temperature (Tg and melt temperature (Tm) of some dlcumyl peroxide cured block polymers of e-caprolactone, styrene and butadiene were determined on the Rheovlbron at 11 Hz. Some of the results are listed In the last two columns of Table II and IV. 

Converting the "living" prepolymer from oxyl-llthlum to oxy-alumlnum chain end can successfully eliminate the undeslred trans-esterlflcatlon In the e-caprolactone ring-opening polymerization and Its more uniform block polymers with styrene and butadiene were thus prepared. 

Figure 2 Example polymers that can undergo phase separation, (a) Poly(ethylene oxide)-f)-poly(butylene oxide), (PEO-f)-PBO) (b) poly(ethyleneoxide)-fc-poly(styrene), (PEO-i>-PS) (c) poly(styreneFi -poly(4-vinylpyridine), (PS-i>-P4VP) (d) poly(ethylene oxide)-f)-poly(caprolactone), (PEO-fc-PCL) (e) poly(ethylene oxide)-f)-poly(butadiene), (PEO-f)-PB) and (f) polyfacrylic acid)-fc-poly(styrene), (PAA-1>-PS).

Formation of a polymer alloy is a common way to improve the property of PLLA. Many kinds of polymers such as polyethylene [70], polypropylene (PP), polystyrene (PS) [71], poly (methyl methacrylate) [72], bisphnol-A type polycarbonate, poly(E-caprolactone), poly(3-hydroxybuty-rate), poly (butylene succinate) (PBS) [73], poly(butylene succinate/adipate) (PBSA), acrylonitrile-butadiene-styrene have been used for preparing PLLA alloys, and some of which have been commercialized. However, there has been no discussion of the thermal degradation behavior of the PLLA component. 

Fig. 6.12 Plot of melting temperature against characteristic ratio for indicated polymers. (1) Polyethylene (2) i-poly(propylene) (3) i-poly(isopropyl acrylate) (4) s-poly(isopropyl acrylate) (5) i-poly(methyl methacrylate) (6) s-poly(methyl methacrylate) (7) poly(dimethyl siloxane) (8) poly(diethyl siloxane) (9) poly(dipropyl siloxane) (10) poly(cis-l,4-isoprene) (11) poly(trans-l,4-isoprene) (12) poly(cis-1,4-butadiene) (13) poly(trans-1,4-butadiene) (14) poly(caprolactone) (15) poly(propiolactone) (16) poly(pivalolactone) (17) poly(oxymethylene) (18) poly(ethylene oxide) (19) poly(trimethylene oxide) (20) poly(tetramethylene oxide) (21) poly(hexamethylene oxide) (22) poly(decamethylene oxide) (23) poly(hexamethylene adipamide) (24) poly(caprolaetam) (25) poly(ethylene terephthalate) (26) poly(ethylene sulfide) (27) poly(tetrafluoroethylene) (28) i-poly(styrene) (29) poly(acrylonitrile) (30) poly(l,3-dioxolane) (31) poly(l,3-dioxopane) (32) poly(l,3-dioxocane) (33) bisphenol A-poly(carbonate).

Although the reactivity increase caused by crown ethers and cryptands in anionic polymerizations has already found a wide range of application, more details have been reported and a number of questions concerning the type and the behavior of the different species present, both in the initiation and in the propagation steps, have been clarified by, for example, kinetic studies [235], Special polymerization reactions that were effected in the presence of crown compounds are those starting with butadiene, propene, styrene, 2-vinyl pyridine, ethylene oxide, propylene sulfide, isobutylene sulfide, methyl methacrylate, p-propyllactone, or e-caprolactone as monomers and alkali metals as initiators [238-246],... 

FTIR spectroscopy has been applied in the study of polymer blends including Neoprene rubber, chlorosulfonated PE, nitrile rubber, polyvinyl chloride (PVC) containing carbon black and other fillers [86], Nylon 6 inorganic [87], polyhydroxyether sulfone/poly(N-vinyl pyrrolidone) [88], graphite-based low-density polyethylene [89], caprolactone/Nafion blends [90], polybutylene terephthalate/polyamide [91], polyphenylene sulfide/acrylonitrile - butadiene - styrene [92], PMMA/polypyrrol [93], and lower or high performance liquid chromatography (LDPE/HDPE) [94]. 

---