The effect of expansion conditions on the batch foaming dynamics of St–MMA copolymer

In this study, we synthesized styrene–methyl methacrylate copolymer particles by suspension polymerization process to study the foaming dynamics via visual batch foaming apparatus. The weight ratio of styrene–methyl methacrylate was 53–47. The foaming system consisted of a self-sealing observation cell equipped with two glass windows and a stereo microscope attached with a high-speed digital camera as well as a pressure and temperature controller. The required pentane pressure was supplied by heating a small pentane flask. The synthesized copolymer particles impregnated by pentane and then the foaming dynamics were recorded after a rapid pressure release. The effect of different foaming conditions, such as temperature, impregnation time, and impregnation pressure on the expansion ratio of styrene–methyl methacrylate copolymer was investigated. It was concluded that impregnation pressure, time, and temperature have different effects on the foaming ratio at impregnation pressures lower and higher than 4 bar.

[1]  J. Kim,et al.  Thermally Expandable Microcapsules for Polymer Foaming—Relationship Between Expandability and Viscoelasticity , 2010 .

[2]  F. Abbasi,et al.  Thermo-oxidative degradation of MMA-St copolymer and EPS lost foams : Kinetics study , 2009 .

[3]  M. Nasiri,et al.  Preparation and Characterization of Expandable St/MMA Copolymers Produced by Suspension Polymerization , 2009 .

[4]  M. Zhan,et al.  Visualization Study of Foaming Process for Polyimide Foams and Its Reinforced Foams , 2008 .

[5]  Chul B. Park,et al.  Measurement of the PVT property of PP/CO2 solution , 2008 .

[6]  F. Abbasi,et al.  Non-isothermal degradation kinetics of MMA-St copolymer and EPS lost foams , 2008 .

[7]  K. Taki.  Experimental and numerical studies on the effects of pressure release rate on number density of bubbles and bubble growth in a polymeric foaming process , 2008 .

[8]  D. Visco,et al.  A review of physical and kinetic models of thermal degradation of expanded polystyrene foam and their application to the lost foam casting process , 2007 .

[9]  J. Košek,et al.  Dynamics of Foaming of Polystyrene Particles , 2006 .

[10]  R. G. Fenton,et al.  Computer Simulation of Bubble-Growth Phenomena in Foaming , 2006 .

[11]  Chul B. Park,et al.  A Microcellular Foaming Simulation System with a High Pressure-Drop Rate , 2006 .

[12]  Takashi Nakayama,et al.  Visual Observations of Batch and Continuous Foaming Processes , 2003 .

[13]  K. R. Doolan.  Nuclear magnetic relaxation in polyolefin resins , 2002 .

[14]  D. Wan,et al.  Controllable radical copolymerization of styrene and methyl methacrylate using 1,1,2,2-tetraphenyl-1,2-bis(trimethylsilyloxy) ethane as initiator , 2001 .

[15]  M. Ohshima,et al.  Polymeric Foaming Simulation for Extrusion Processes , 2001 .

[16]  D. Venerus.  Diffusion-induced bubble growth in viscous liquids of finite and infinite extent , 2001 .

[17]  J. Wootthikanokkhan,et al.  Effects of reaction conditions on poly(methyl methacrylate) polymerized by living radical polymerization with iniferter , 2000 .

[18]  J. Honerkamp,et al.  EVALUATION OF MODELS COMBINING RHEOLOGICAL DATA WITH THE MOLECULAR WEIGHT DISTRIBUTION , 1998 .

[19]  Chul B. Park,et al.  Microcellular sheet extrusion system process design models for shaping and cell growth control , 1998 .

[20]  Barry Bernstein,et al.  Analysis of diffusion-induced bubble growth in viscoelastic liquids , 1998 .

[21]  J. Koller,et al.  Structure of Styrene and Acrylate Block Copolymers , 1996 .

[22]  Chul B. Park,et al.  Effect of the pressure drop rate on cell nucleation in continuous processing of microcellular polymers , 1995 .

[23]  G. Campbell,et al.  The heterogeneous nucleation of microcellular foams assisted by the survival of microvoids in polymers containing low glass transition particles. Part II: Experimental results and discussion , 1994 .

[24]  D. Mead.  Determination of molecular weight distributions of linear flexible polymers from linear viscoelastic material functions , 1994 .

[25]  김병규,et al.  Molecular Weight and Molecular Weight Distribution From Dynamic Measurements of Polymer Melts , 1988 .

[26]  D. S. Pearson,et al.  Theory of Polydispersity Effects on Polymer Rheology. Binary Distribution of Molecular Weights , 1987 .

[27]  G. Marrucci.  Relaxation by reptation and tube enlargement: A model for polydisperse polymers , 1985 .

[28]  C. Macosko,et al.  Bubble growth and collapse in viscoelastic liquids analyzed , 1984 .

[29]  C. Han,et al.  Studies on structural foam processing. III. Bubble dynamics in foam extrusion through a converging die , 1981 .

[30]  C. Han,et al.  Studies on structural foam processing II. Bubble dynamics in foam injection molding , 1978 .

[31]  C. Han,et al.  Studies on structural foam processing I. The rheology of foam extrusion , 1978 .

[32]  Alan N. Gent,et al.  Nucleation and Growth of Gas Bubbles in Elastomers , 1969 .