Ultrasonically aided extrusion of natural rubber (NR), styrene butadiene rubber (SBR), and NR/SBR blends with ratio of 70/30, 50/50, and 30/70 were carried out at various ultrasonic amplitudes up to 10 μm. A die pressure of NR and NR/SBR blends continuously decreased with increase of ultrasonic amplitude, while that of SBR showed a slight increase with increase in amplitude from 5.0 to 7.5 μm due to a dominant effect of SBR gel formation. Complex dynamic viscosity, minimum and maximum torque of curing curves of NR, SBR, and NR/SBR blends, and cross-link density and gel fraction of their vulcanizates were decreased by the ultrasonic treatment at an amplitude of 10 μm, due to the molecular chain scission. The latter also led to a decrease in the hardness, modulus at a strain of 100%, and abrasion resistance of NR and NR/SBR blends. However, the modulus and abrasion resistance of SBR showed an improvement at amplitude of 7.5 μm, dueto a dominant effect of gel formation. Both the tensile strength and elongation at break of ultrasonically treated NR/SBR blends showed a maximum at amplitude of 5.0 μm, with the modulus at a strain of 100% not being affected. Morphological studies using the phase-contrast optical microscope and atomic force microscopy showed a reduction in the size of rubber phases and a better homogeneity of NR/SBR blend by the ultrasonic treatment at amplitude of 5.0 μm. Accordingly, the increase in both the tensile strength and elongation at break of ultrasonically treated NR/SBR blends at an amplitude of 5.0 μm is mainly ascribed to the lower size of rubber phases and improved uniformity of blend caused by the ultrasonic treatment.
BernhardtEC. Effect of ultrasound on thermoplastic melts. Ind Eng Chem1954; 46(4): 742–746.
2.
FridmanMLPeshkovskySL. Molding of polymers under conditions of vibration effects. Adv Polym Sci1990; 93: 41–79.
3.
PeshkovskiiSLFriedmanMLTukachinskiiAIVinogradovGVEnikolopianNS. Acoustic cavitation and its effect on flow in polymers and filled systems. Polym Compos1983; 4(2): 126–134.
4.
IsayevAIWongCMZengX. Effect of oscillations during extrusion on rheology and mechanical properties of polymers. Adv Polym Technol1990; 10(1): 31–45.
5.
IsayevAIChenJTukachinskyA. Novel ultrasonic technology for devulcanization of waste rubbers. Rubber Chem Technol1995; 68(2): 267–280.
6.
IsayevAIGhoseSUltrasonic devulcanization of used tires and waste rubbers. In: DeSKIsayevAIKhaitK (eds) Rubber recycling. Boca Raton, FL: CRC, 2005, pp. 327–400.
7.
ChenGGuoSLiH. Ultrasonic improvement of the compatibility and rheological behavior of high-density polyethylene/polystyrene blends. J Appl Polym Sci2002; 86(1): 23–32.
8.
ChenGGuoSLiY. Dynamic rheological properties of high-density polyethylene/polystyrene blends extruded in the presence of ultrasonic oscillations. J Appl Polym Sci2004; 92(5): 3153–3158.
9.
KimHLeeJW. Effect of ultrasonic wave on the degradation of polypropylene melt and morphology of its blend with polystyrene. Polymer2002; 43(8): 2585–2589.
10.
IsayevAIHongCKKimKJ. Continuous mixing and compounding of polymer/filler and polymer/polymer mixtures with the aid of ultrasound. Rubber Chem Technol2003; 76(4): 923–947.
11.
IsayevAIHongCK. Novel ultrasonic process for in-situ copolymer formation and compatibilization of immiscible polymers. Polym Eng Sci2003; 43(1): 91–101.
12.
ChenYCaoYLiH. Effect of ultrasound on extrusion of polypropylene/ethyl ene-propylene-diene terpolymer blend: processing and mechanical properties. J Appl Polym Sci2003; 90(13): 3519–3525.
13.
FengWIsayevAI. In-situ ultrasonic compatibilization of unvulcanized and dynamically vulcanized PP/EPDM blends. Polym Eng Sci2004; 44(11): 2019–2028.
14.
FengWIsayevAI. In situ compatibilization of PP/EPDM blends during ultrasound aided extrusion. Polymer2004; 45(4): 1207–1216.
15.
ChenYLiH. Effect of ultrasound on extrusion of PP/EPDM blends: structure and mechanical properties. Polym Eng Sci2004; 44(8): 1509–1513.
16.
ChenYLiH. Phase morphology evolution and compatibility improvement of PP/EPDM by ultrasound irradiation. Polymer2005; 46(18): 7707–7714.
17.
OhJSIsayevAIRogunovaMA. Continuous ultrasonic process for in situ com patibilization of polypropylene/natural rubber blends. Polymer2003; 44(8): 2337–2349.
18.
LiuGLiH. Extrusion of ultrahigh molecular weight polyethylene under ultrasonic vibration field. J Appl Polym Sci2003; 89(10): 2628–2632.
19.
WuHGuoSChenGShiH. Effects of ultrasonic oscillations on processing behavior and mechanical properties of metallocene-catalyzed linear low-density polyethylene/low-density polyethylene blends. J Appl Polym Sci2004; 94(6): 2522–2527.
20.
WuHGuoSLiZ. Effects of ultrasonic oscillations on linear viscoelastic behaviors of metallocene-catalyzed linear low density polyethylene and its blends with low density polyethylene. J Polym Sci B: Polym Phys2005; 43(21): 3030–3043.
21.
LiJLiangMGuoSKuthanovaVHausnerovaB. Linear viscoelastic properties of high-density polyethylene/polyamide-6 blends extruded in the presence of ultrasonic oscillations. J Polym Sci B: Polym Phys2005; 43(10): 1260–1269.
22.
LiJGuoSSlezakRHausnerovaB. In situ compatibilization of PS/EPDM blends during ultrasonic extrusion. Macromol Chem Phys2005; 206(24): 2429–2439.
23.
LiJGuoSLiangM. Effects of ultrasonic oscillation on processing behaviors of PS, EPDM, and PS/EPDM blend. J Appl Polym Sci2006; 100(3): 1856–1863.
24.
LinHIsayevAI. Ultrasonic treatment of polypropylene, polyamide 6, and their blends. J Appl Polym Sci2006; 102(3): 2643–2653.
25.
LeeSLeeYLeeJ. Effect of ultrasound on the properties of biodegradable polymer blends of poly(lactic acid) with poly(butylene adipate-co-terephthalate). Macromol Res2007; 15(1): 44–50.
26.
JiangGWuHXieTGuoS. Improved processing behaviors and mechanical properties of polyolefin elastomer blends prepared by ultrasound-assisted extrusion. J Appl Polym Sci2009; 112(4): 2136–2142.
27.
XieTWuHBaoWGuoSChenYHuangH. Enhanced compatibility of PA6/POE blends by POE-g-MAH prepared through ultrasound-assisted extrusion. J Appl Polym Sci2010; 118(3): 1846–1852.
28.
WuHBaoWGuoS. Enhanced flow behaviors of metallocene-catalyzed linear low-density polyethylene during ultrasound-assisted extrusion. Polym Eng Sci2010; 50(11): 2229–2235.
29.
GunesKIsayevAI. Ultrasonic treatment of PET/LCP blends during extrusion. Int J Polym Technol2009; 1: 1–15.
30.
GunesKIsayevAI. In situ compatibilization of PEN/LCP blends by ultrasonic extrusion. J Appl Polym Sci2011; 122(1): 354–365.
31.
GunesKIsayevAILiXWesdemiotisC. Fast in situ copolymerization of PET/PEN blends by ultrasonically-aided extrusion. Polymer2010; 51(5): 1071–1081.
32.
GunesKIsayevAI. Ultrasonically-aided extrusion of blends of two thermotropic LCPs. Polym Sci Ser A Polym Phys2010; 52(11): 1124–1136.
33.
IsayevAIHongCK. Ultrasound assisted continuous process for making polymer blends and copolymers. Appl. No. 09/784,374 (Feb 2001), Patent No. 6,528,554, USA, 2003.
FengWIsayevAI. High-power ultrasonic treatment of butyl rubber gum: structure and properties. J Polym Sci B: Polym Phys2004; 43(3): 334–344.
36.
IsayevAIKimSHFengW. Continuous ultrasonic treatment of uncured and sulfur cured SBR: effect of styrene content. Rubber Chem Technol2005; 78(4): 606–619.
37.
OhJSGhoseSIsayevAI. Effects of ultrasonic treatment on unfilled butadiene rubber. JPolym Sci B: Polym Phys2003; 41(22): 2959–2968.
38.
YunJIsayevAI. The effect of high power ultrasound on EPDM gum in extrusion process. J Appl Polym Sci2007; 105(6): 3698–3707.
39.
WaltersMHKeyteDN. Heterogeneous structure in blends of rubber polymers. Trans Inst Rubber Ind1962; 38(2): T40–T55.
40.
HessWMScottCECallanJE. Carbon black distribution in elastomer blends. Rubber Chem Technol1967; 40(2): 371–384.
41.
MarshPAVoetAPriceLD. Electron microscopy of heterogeneous elastomer blends. Rubber Chem Technol1967; 40(2): 59–70.
42.
CallanJEHessWMScottCE. Elastomer blends. Compatibility and relative response to fillers. Rubber Chem Technol1971; 44(3): 814–837.
43.
HessWM. Characterization of dispersions. Rubber Chem Technol1991; 64(3): 386–449.
44.
BarGGanterMBrandschRDelineauLWhangboMH. Examination of butadiene/ styrene-co-butadiene rubber blends by tapping mode atomic force microscopy. Importance of the indentation depth and reduced tip-sample energy dissipation in tapping mode atomic force microscopy study of elastomers. Langmuir2000; 16(13): 5702–5711.
45.
JeonIHKimHKimSG. Characterization of rubber micro-morphology by atomic force microscopy (AFM). Rubber Chem Technol2003; 76(1): 1–11.
46.
WangCCDonnetJBWangTKPontier-JohnsonMWelshF. AFM study of rubber compounds. Rubber Chem Technol2005; 78(1): 17–27.
47.
TsouAHWaddellWH. Morphology of elastomer blends by dynamic AFM. Kautsch Gummi Kunstst2002; 55(7–8): 382–387.
48.
AchallaPMcCormickJHodgeTMorelandCEsnaultPKarimA. Characterization of elastomeric blends by atomic force microscopy. JPolym Sci B: Polym Phys2006; 44(3): 492–503.
49.
LeHHIlischSHeidenreichDWutzlerARaduschHJ. Kinetics of the phase selective localization of silica in rubber blends. Polym Compos2010; 31(10): 1701–1711.
50.
TukachinskyASchwormDIsayevAI. Devulcanization of waste tire rubber by powerful ultrasound. Rubber Chem Technol1996; 69: 92–103.
51.
KimSHLevinVYIsayevAI. Effect of carbon black on the ultrasound devulcanization of sulfur cured SBR vulcanizates. Paper #99 presented at the 152nd meeting of the ACS Rubber Division, Cleveland, OH, 1997.
52.
KrausG. Interactions between elastomers and reinforcing fillers. In: KrausG (ed) Reinforcement of elastomers. New York, NY: John Wiley & Sons, Inc., 1965, pp. 125–152.
53.
ChenYLiH. Mechanism for effect of ultrasound on polymer melt in extrusion. J Polym Sci B: Polym Phys2007; 45(10): 1226–1233.
54.
ChenYLiH. Effect of ultrasound on the viscoelasticity and rheology of polystyrene extruded through a slit die. J Appl Polym Sci2006; 100: 2907–2911.
55.
IsayevAIWongCMZengX. Flow of thermoplastics in an annular die under orthogonal oscillations. J Non-Newtonian Fluid Mech1990; 34: 375–397.
NelsonCJAvgeropoulosGNWeissertFCBohmGGA. The relationship between rheology, morphology and physical properties in heterogeneous blends. Angew Makromol Chem1977; 60(1): 49–86.
