Preparation and foamability of high melt strength polypropylene based on grafting vinyl polydimethylsiloxane and styrene

A novel strategy was developed by melt grafting reaction in the presence of macromonomer vinyl polydimethylsiloxane (VS) and comonomer styrene (St) for preparing high melt strength polypropylene (HMSPP), and the rheological behavior, melt strength, and foaming ability of HMSPP were investigated. The results showed that VS and St were successfully grafted onto isotactic polypropylene (iPP), and the melt strength of HMSPP increased by more than 12 times compared to that of the virgin iPP. Moreover, HMSPP exhibited excellent foaming ability with smaller cell size, higher cell density, and higher expansion ratio compared to the virgin iPP when supercritical carbon dioxide was used as the blowing agent. POLYM. ENG. SCI., 55:251–259, 2015. © 2014 Society of Plastics Engineers

[1]  Guoli Wang,et al.  Synthesis, characterization, and properties of long‐chain branched poly(butylene succinate) , 2012 .

[2]  W. Yuan,et al.  Determination of CO2 solubility in isotactic polypropylene melts with different polydispersities using magnetic suspension balance combined with swelling correction , 2012 .

[3]  T. Tang,et al.  A new grafting monomer for synthesizing long chain branched polypropylene through melt radical reaction , 2012 .

[4]  S. Sengupta,et al.  Silane grafting and moisture crosslinking of polypropylene , 2011 .

[5]  Li Bing,et al.  Batch Foam Processing of Polypropylene/Polydimethylsiloxane Blends , 2010 .

[6]  T. Tang,et al.  Controlling melt reactions during preparing long chain branched polypropylene using copper N,N-dimethyldithiocarbamate , 2010 .

[7]  Huining Xiao,et al.  The melt grafting preparation and rheological characterization of long chain branching polypropylene , 2009 .

[8]  M. Jollands,et al.  Foaming behavior of high-melt strength polypropylene/clay nanocomposites , 2009 .

[9]  Zhiqiang Fan,et al.  Structure and Rheological Properties of the Products of Solid-State Graft Polymerization of Styrene in Annealed Polypropylene Reactor Granules , 2009 .

[10]  Kun Cao,et al.  Synthesis and characterization of high-density polypropylene-grafted polyethylene via a macromolecular reaction and its rheological behavior , 2009 .

[11]  Yuan Hu,et al.  Influence of Coagents on the Silane Grafting and Cross-linking of Polypropylene , 2009 .

[12]  T. Tang,et al.  Characterization of high melt strength polypropylene synthesized via silane grafting initiated by in situ heat induction reaction , 2008 .

[13]  Jian Yu,et al.  Foaming behavior of isotactic polypropylene in supercritical CO2 influenced by phase morphology via chain grafting , 2008 .

[14]  P. Cassagnau.  Melt rheology of organoclay and fumed silica nanocomposites , 2008 .

[15]  T. Peijs,et al.  POSS GRAFTING ON PPgMA BY ONE-STEP REACTIVE BLENDING , 2009 .

[16]  Wei Yu,et al.  The preparation and rheology characterization of long chain branching polypropylene , 2006 .

[17]  P. Godard,et al.  A sensitive method to detect very low levels of long chain branching from the molar mass distribution and linear viscoelastic response , 2005 .

[18]  Jae Wook Lee,et al.  Effect of long‐chain branches of polypropylene on rheological properties and foam‐extrusion performances , 2005 .

[19]  K. Sirisinha,et al.  Properties and Characterization of Filled Poly(Propylene) Composites Crosslinked Through Siloxane Linkage , 2005 .

[20]  F. Ciardelli,et al.  Control of Degradation Reactions during Radical Functionalization of Polypropylene in the Melt , 2004 .

[21]  C. Macosko,et al.  Block Copolymer Micelles for Nucleation of Microcellular Thermoplastic Foams , 2004 .

[22]  A. Gotsis,et al.  The effect of long chain branching on the processability of polypropylene in thermoforming , 2004 .

[23]  Chul B. Park,et al.  Effects of die geometry on cell nucleation of PS foams blown with CO2 , 2003 .

[24]  D. Graebling.  Synthesis of Branched Polypropylene by a Reactive Extrusion Process , 2002 .

[25]  N. Hadjichristidis,et al.  Well-Defined, Model Long Chain Branched Polyethylene. 2. Melt Rheological Behavior , 2002 .

[26]  F. Ciardelli,et al.  Monitoring the chemical crosslinking of propylene polymers through rheology , 2002 .

[27]  C. Friedrich,et al.  Van Gurp-Palmen Plot II – classification of long chain branched polymers by their topology , 2002 .

[28]  A. Gotsis,et al.  Rheological Characterization of Long Chain Branching in a Melt of Evolving Molecular Architecture , 2001 .

[29]  Ying Li,et al.  Study on styrene-assisted melt free-radical grafting of maleic anhydride onto polypropylene , 2001 .

[30]  J. Dealy,et al.  Effect of Molecular Structure on the Linear Viscoelastic Behavior of Polyethylene , 2000 .

[31]  C. Mijangos,et al.  Silane grafting and moisture crosslinking of polypropylene , 2000 .

[32]  Ning Liu,et al.  Influences of grafting formulations and processing conditions on properties of silane grafted moisture crosslinked polypropylenes , 2000 .

[33]  G. Hu,et al.  Styrene-assisted melt free radical grafting of glycidyl methacrylate onto polypropylene , 1998 .

[34]  C. Tzoganakis,et al.  Chemical modification of polypropylene with peroxide/pentaerythritol triacrylate by reactive extrusion , 1996 .

[35]  E. Beckman,et al.  Generation of microcellular polymeric foams using supercritical carbon dioxide. I: Effect of pressure and temperature on nucleation , 1994 .

[36]  K. J. Kim,et al.  Cross‐Linking of polypropylene by peroxide and multifunctional monomer during reactive extrusion , 1993 .

[37]  N. Suh,et al.  A process for making microcellular thermoplastic parts , 1990 .