Polymer Suspension Based Shear Thickening Fluid Fabric

Polymer Suspension Based snip knob Fluid FabricPolymer hanging based dress boss legato- material for protective applications was a vernal mind. crop guest fluent was in any case known as STF. Generally STF contains liquid medium and solid sh atomic number 18s which stick out be inorganic or organic based. Basically, the viscosity of the Shear Thickening Fluid (STF) ordain be profit when clip try on increasing. By exploiting this fluid deorganization from STF, for the material itself, the friction amid train of thought-yarn and fiber-fiber leave alone be increased drastically when take out employ all all over the fabric involved. Then, the fabric itself ordain be having higher aptitude absorption when STF impregnated with the fabric itself compargond with un-impregnated fabric confused.The reason for this selection was motivated by precedent works in this scope, as well as the beneficial characteristics provided by these cardinal temporals. US Patent s 5599290 and 5545128 withstand developed B unrivalled fracture prevention garment and method. In these two works, carried out by the resembling authors, the patent outlines a design procedured to resolve the issue of the harmful make of impacts on the finger cymbals of elderly individuals. This design was described as being composed of the fol down(p)ing the component includes a dilatant material that was relatively stiff practiced the time of impact and relatively fluid at other times. In a p preservered embodiment, the invention provides a hip pad, possessing a thickness small enough to be compatible with we ber acceptability, that conforms to the shape of the body during e very(prenominal)(prenominal)day activities such(prenominal) as walking, sitting, and sleeping, and was thus comfortable to the wearer (5-14).In align to model the rheologic port of these fluids, it has been proposed to use a great power play law analysis with the relationship amid the viscosity and soak wander represented by = k n-1Where k is the fluids consistency and n is the power law exponent specific to the region of high or low viscosity. According to Barnes, the dress-thinning and pluck- change regions mint be accounted for by, using the sum of two power laws, with one value of n less(prenominal) than unity and one greater. (8)The rheology studied pass on be focused on colloidal rift rather than hard jot suspension. Hard jot suspension like silica pinch, was extensively studied by many researched over the world like Wagner and lee(prenominal) Barnes (5 8) .They claimed, the hard corpuscle hang up in the polyethylene glycol (flattop fluid) allow for exhibit shear modify fashion by varying the script cipher of the particle over letter carrier fluid from, above 40% to 55%. 30% by record book fraction depart non exhibit shear inspissate demeanour but in Ragvahan look intos showed (10), by using 10% volume fraction of fumed silica suspended in the Polypropylene glycol (PPG), shear thickening appearance had occurred but likely referred to particle agglomeration( flocculated gel) rather than hydrocluster because fumed silica, naturally have low bulge area and larger particle sizing. In the experiment, the attack renewal called censorious shear rate seems having two points, the higher and the trim down shear strain, payable to the original building of the carrier fluid itself (polypropylene glycol). The administration of vinyl group and straight chain in PPG gave two systems of clusters (10).Colloidal suspension conceive was not stress and thoroughly studied because of the complexity of the colloidal inhabits itself, which unremarkably involved many factors such as steric and electrostatic stabilize, stability of the suspension and the formation of the hydrocluster via modification of the interaction particle of the colloidal suspension. In chapter 2, theoretic discussion about colloidal suspension which contribu ted to the new phenomenon of Shear Thickening Fluid (STF) such as structure-relationship of the colloidal suspension in polymer solution and self-coloured/Liquid transition (SLT) and also liquid/Solid transition (LST) 17. According to the DVLO theory, stabilization of particle in the suspension with steric and electrostatic (will be have detail explanation in the chapter 2) cares are great nationments to be investigated. The colloid particles were also known as surface charge particle. It involved the attraction and repulsive force for every single particle in the colloid dispersion or suspension, which contributed to the shear thickening conduct of the STF.In this publisher, colloidal suspension rheology will be main topics, by relating it with the structure-relationship and LST theory. In the chapter 2, more detailed flack transition of STF will be extensively discussed. Conventionally, the plan of attack transition involved Order-Disorder transition (ODT) and hydrocluster .The main criteria in Shear Thickening Fluid (STF) were to predict tiny shear rate which was the critical point when the particles were suspended in the STF. It started to cluster with each other, exhibiting shear thickening way upon increase in shear rate. on that point were many factors in STF, both(prenominal) of them were, volume fraction colony (between particle and carrier fluid), particle shape and size dependence (porosity) and particle interaction dependence. The particles can be normal charge (hard particle such as fumed silica, clay and any metal oxide particle) or colloidal particle (with charge).In this paper, fumed silica will be used as a main material for hard particle as well as and colloid dispersion. fume silica will be turned into colloidal suspension by surrounding the charging over its surface particle. The main atomic number 82 of colloidal suspension for this study was based on DVLO theory. Therefore, by studying the electrokinetic for each suspension, relation between this study with measured rheology through the power law index and yield stress value, there are possibilities to relate the structure- relationship in colloidal suspension of STF with onset transition (SLT LST) evaluated. There were two rudimentary requirements for exhibiting shear thickening behavior from colloidal suspension raghavan, wagner, barnes, firstly, the volume fraction of the solid in the suspension must be very high and secondly, suspension must be nonflocculated or deflocculatedSTF Fabric composite will be impregnated with STF has great potential in bullet proof application especially for nuts armor. The vest will be having higher flexibility and less heavy than conventional soft armor. Wagner and his aggroup claimed, STF will increase the friction between yarn-yarn and fiber-fiber by 500% using pull out yarn psychometric test. Also, by using NIJ as reference stabbed and puncture resistance test (NIJ 115.00) for STF Fabric composite, it easily p assed level 1 protection. For the bullet test, also NIJ as reference, it showed interesting results. Instead of higher penetration from the bullet (9mm) to the conventional fabric composite, for STF-Fabric composite, bullet was deflected away (rebound) and had less significant point out over the top of the clay in tested frame panel. Basically, fabric composite will be placed over the top of the clay. The mark of the clay will be used as reference for the dissipated energy (energy absorption) from the test. A big diameter of the mark and the depth for the mark was deeper indicating the fabric composite has a low dissipated energy system. Smaller diameter of the mark and less depth of the indented clay, showed, a higher dissipated energy system for the fabric composite.1.2 Problem StatementWagner found that STF had rheological characteristic of dilatant but studied on the use of hard particle in suspension. Colloidal suspension of fume silica in polymeric sedimentary media was perf ormed by other researcher but they studied only ionic strength and critical shear rate incumbrance. In depth study on formation of hydroclusters in colloid need to evaluated to relate structure relationship between shear thickening behavior of polymer suspension with regard to composition (volume fraction), particle porosity, size and shape of particle. Hence, viscosity measurements were evaluated for different polymer systems to determine the effect of these systems on critical shear rate and shear thickening phenomena. Stabbed and puncture resistant fabric composite employing STF with high spike and knife impact instruction execution can be affected by the formulation of STF and adhesion between STF suspension and fabric yarn. Hence, this study is hoped to solve the problems faced by indepth at a deject placestanding on rheological and executing aspects in the development of STF fabric composite for protective applications.1.3 Objectives Of StudyThe specific objectives of the project includeTo determine physical colloid properties of colloidal suspension from hard line of business particles and colloidal dispersion via zeta potential studies.To determine the rheological behaviors of the colloidal suspension from the effects of repulsion system present during steady shear experiments.To fabricate STF fabric composite using respective(a) layers of Kevlar 49 and cotton fabric and determine stab and puncture resistance of STF fabric composite match to standard NIJ 115.00 tests.ReferencesBazhenov, S. (1997). Dissipation of Energy by Bulletproof Aramid Fabric. ledger of Materials. Science, 32, 4167-4173.Cunniff, P. (1992An Analysis of the System Effects in Woven Fabrics Under Ballistic Impact, Textile Research Journal, 62, 495-5093. Egres Jr., R. (2005). Stab performance of shear thickening fluid (STF)-fabric compositesfor body armor applications. International SAMPE Symposium and Exhibition, 50, 2369-2380.4. Lee, Y. (2003). The ballistic impact characte ristics of Kevlar woven fabrics impregnated with a colloidal shear thickening fluid. Journal of materials science, 38(13), 2825-2833Maranzano, B.J. and Wagner, N.J., ( 2001) The effects of interparticle interactions and particle size on reversible shear thickening hard-sphere colloidal dispersions, Journal of Rheology, 45(5), 1205-1222, 2001Maranzano, B.J., Wagner, N.J., Fritz, G., Glatter, O., (2000) Surface charge of 3-(trimethoxysilyl)propyl methacrylate (TPM) coated Stber silica colloids by zeta-phase analysis light scattering and small tip off neutron scattering, Lagmuir 16, 10556-10558.Maranzano, B.J., Wagner, N.J. (2001), the effects of particle size on reversible shear thickening of concentrated colloidal dispersions, J. Chem. Phys. 114 10514-10527.Barnes HA (1989) Shear-thickening (dilatancy) in suspensions ofnonaggregating solid particles dispersed in Newtonian liquids. J Rheology, 33, 329-366I.F.Efremov, The Dilatancy of Colloidal Structures and Polymer Solutions Transla ted from Uspekhi Khimii, 51 285-310 (1982), Russia Chemical Reviews, 51 (2), 1982SRINIVASA R. RAGHAVAN AND SAAD A. KHAN Department of Chemical Engineering, North Carolina State University, Raleigh, North Carolina 27695-7905G. Fritz, B. J. Maranzano, N. J. Wagner, N. Willenbacher 2002, High frequency rheology of hard sphere colloidal dispersions measured with a torsional resonator, Journal of Non-Newtonian Fluid Mechanics, 102, 2, pp 149-156J. Schuster, D. Heider, K. Sharp, M. Glowania, 2008, Thermal conductivities of three-dimensionally woven fabric composites Composites Science and Technology, 68, 9, pp 2085-2091 recent Sil Lee Norman J. Wagner Dynamic properties of shear thickening colloidal suspensions Rheol Acta (2003) 42 199-208Hoffman RL (1974) Discontinuous and dilatant viscosity behavior in concentrated suspensions. II. Theory and experimental tests. J Colloid Interface Sci 46491-506Hoffman RL (1997) Explanations for the cause of shear thickening in concentrated colloidal su spensions. J Rheology 42111-123Egres, R.G., Lee, Y.S., Kirkwood, J.E., Kirkwood, K.M., Wetzel, E.D., and Wagner, N.J. 2003. Novel flexible body armor utilizing shear-thickening fluid (STF) composites. Proceedings of 14th International Conference on Composite Materials. San Diego, CA.July 14 18, 2003.Horst Henning Winter et. Al Rheology of Polymers near Liquid-Solid TransitionsCHAPTER TWOLITERATURE REVIEW2.1 Shear Thickening Fluid (STF) Introduction ReviewShear thickening fluid, basically have two different types of fluid behavior shear thinning and shear thickening. There are two types of shear thickening behavior in the fluid behavior. First, Shear thickening is a non-Newtonian flow behavior (dilatant) observed as an increase in viscosity with increasing shear rate or applied stress also known as time independent material (Barnes, 1989 Maranzano and Wagner, 2001 Lee and Wagner, 2003). Non-Newtonian flow behavior (rheopectics) observed as an increase in viscosity with increasing d uration of stress (shear rate constant) known as the time dependent materials which have a memory to deform over period of time ( figure 1).Concentrated colloidal suspensions consisting of solid/hard spheres particles dispersed in a carrier liquid have been shown to exhibit rheological shear thickening behavior resulting in large, sometimes discontinuous increases in viscosity above a critical shear rate. This transition from a silken liquid to a solid-like material is collectible to the formation of shear induced transient aggregates, or hydroclusters, that dramatically increase the viscosity of the fluid (Barnes, 1989 Maranzano and Wagner, 2001 Lee and Wagner, 2003). For stabilize the STF and avoiding agglomeration behavior, co-solvent is added and it must be done because STF has a very strong molecule interaction between particles and carrier fluid (attraction force) rather than repulsive force when force is applied at specific time (critical shear rate and critical shear stres s) Barnes, 1989 Maranzano and Wagner, 2001 Lee and Wagner, 2003.The Shear Thickening Fluid (STF) is the combination of the particles suspended in the carrier fluid. Figure 2 showed the STF curve when shear stress applied on the material. The particles used can be made of various materials, such as Silica Dioxide or other oxides, or polymers such as Polystyrene (PS) or Polymethyl methacrylate (PMMA), or other polymers from photographic emulsion polymerization. Generally, particles can be in various shapes like spherical, elliptical, disk-like or clay particles (Barnes, 1989).The particles can be stabilized in solution or dispersed by charge, Brownian motion, grafted polymers and others. Then, pH value of a suspension also contributed to the stability of suspension via colloidal condition such as steric repulsion and electrostatic system. The effects of pH value, concentration of the surfactant, and ionic strength of the surfactant are major factors for the colloidal suspension. This influence disceptation is due to the agglomeration particle size (F. Rey, M.A. Ferreira et al. 1995).These are basic contestations in the rheological suspension and colloidal suspension system. galore(postnominal) studies of shear thickening fluid system (Barnes 1989, Hoffman 1998, Wagner 2004), focus on the colloidal particles only such as nanoparticles colloidal silica and monodisperse silica, which is it is well known as a very stable individual particle interaction in the suspension Brownian suspension.In this paper, electrostatic stabilize and steric repulsion system is used to determine the interparticles interaction in the rheological suspension. Electrostatic stabilize is less studies due to the complexity in the rheological suspension. Concentration and ionic strength of the surfactant are the main parameter of this paper and the final pH value is critical measured in order to exhibit rheological shear thickening. F. Rey, and M.A. Ferreira in their paper Effect of conc entration, pH, and ionic strength on the viscosity of solutions of a soil fulvic acid claims, all the parameter in this studies showed the dramatic instant result of the suspension due to the gel point of the suspension or well known as isoelectric point (iep) by adjusting H+ present in the rheological suspension. in addition of steric repulsion system, make a barriers for the individual surface particle is a invention in this paper. The double layers of the barriers (thickness) due to the zeta potential and electrokinetic theories are independent from the shear stress during rheological experiments. Because of the main intention of this paper are to determine the factors involving onset transition of the STF due to the interparticle interaction dependence which are virtually link up to the colloidal suspension rheology and the effects of the onset transition (rheological behavior) for the stab and puncture resistance test of fabric composite.Then, the co-solvent that are used, it can be aqueous in temperament and non-aqueous which can be elect to stabilize suspension system The co-solvent should be environmentally stable like ethanol and methanol, so that, they remain integral to the fabric and suspended during service. Another function of co-solvent is to lower the viscosity of the STF, so that impregnation dish out of fabric composite becomes efficient and easy. By adjusting the viscosity of the STF, areal density of final fabric composite can be alter and also monitored. The particles must get through and suspended in the fiber-fiber and yarn-yarn lee wagner et al 2003. The result from the good impregnation process is the friction force between yarn-yarn and fiber-fiber will be increased lee wagner et al 2003.But in this paper, by using information from wagner and other researchers, a variation of the drying temperature for the STF and STF- fabric composite will be designed and tested via thermal abasement technique ( pre-degradation) and swelling b ehavior of the STF-fabric composite after at the different drying temperature. The idea are to avoid pre-degradation region and swelling behavior of the STF in the drying process which is believed will reduced the performance of the fabric composite due to the following factors, degradation of the STF and STF-fabric composite due to the drying temperature and swelling behavior of STF. By combination those factors, believed, the internal friction between fiber-fiber and yarn-yarn will be reduced which is making inefficiency of energy absorbtion or dissipated energy for fabric composite (Wagner 2004).2.2 implement of Shear Thickening Fluid (STF)The implement of STF normally can be described via hydrocluster theory and order-disorder theory. The similiarity of these theories is a idea of a new macrostructure formation occurred, furthermore, it are closely related to rheological experiments such as temperature and time factors. A few researchers like Barnes (1989), Hoffman (1998) and wagner (2004), claimed colloidal factors such as different types of carrier fluid, particles porosity, and volume fraction of particle suspended. But, these two theories still cant explain in detail about the mechanism of STF. Wagner and his team claimed the formation of hydrocluster must be a deflocculated suspension and major parmaters of STF are volume fraction, interparticle interaction, and particle porosity. A new theoretical transition will be proposed for STF behavior. Liquid-Solid transition (LST) or semi-solid transition involving the informality state of the fluid during transition which is normally include the changes of loss and storage modulus during transition and believed new formation of a new macrostructure are formed during rheological experiment. This a new macrostructure formed due to the formation of the attraction force and repulsion force in the STF, which is believed closely related with double layer theories in zeta potential theory. LST theories is based on the transition of the material due to the changing of the complex modulus which are can be translated into the formation of gel (stiffness) and relaxation state of the material during near transiton and at the onset transition.2.2.1 HydroclusterThe nigh related theories to the shear thickening behavior are the hydrocluster theory. Basically, the hydrocluster will be occurred when the balance force from prune flow in the concentrated suspension and the force rising from particle particle (interparticles) interaction (Bender and Wagner 1995).There are two conditions, first via colloidal factors (steric and electrostatic repulsion) and particle interactions between particle-particle and particle-carrier fluid (Bender and Wagner 1995). Figure 3 showed the formation of hydrocluster, when the applied shear stress on the STF.The formations of hydrocluster are still extensively investigated by researcher in the entire world. The main interest of this unique behavior is the onset trans ition (critical shear rate) from liquid state to solid or gel state. This phenomenon involving the rapid changes of fluid viscosity in a second whether applied it with shear stress, applied electric field (refer to the ER fluid), and applied magnetic field (refer to the MR fluid). There are specific equipments for detection of this phenomenon such as optical rheometer, small angle neutron scattering (SANS), and two prick light laser scattering. But with all this equipments, still the formation of hydrocluster is unknown phenomena.According to this theory, at the lower stress (below critical stress, maximum volume packing fraction) interparticle interaction either Brownian motion or electrostatic, making the concentrated suspension is easily flow (shear thinning behavior and viscosity of the suspension become lower) due to the particles slippage in the carrier fluid. As the stress is increased, the attraction forces is slightly increases than repulsion force in between particles of the concentrated suspension (particles aggregation become larger and the viscosity of the suspension become higher). When the magnitudes of the shearing force are equilibrium to the interparticle interaction, the particles in the concentrated suspension become cluster also known as hydrocluster.This theory is first suggested by Brady (Bossis and Brady 1989) as a result from stokesian Dynamics simulation and then, supported by optical rheological experiment by wagner (Bender and Wagner 1995). Basically, these phenomenons are closely related with phenomenon of Resonance in physic. In physics, resonance is the tendency of a system to oscillate at greater amplitude at some frequencies than at others. These are known as the systems resonant frequencies (or resonance frequencies). At these frequencies, even small semiweekly driving forces can produce large amplitude oscillations, because the system stores vibration energy the fundamental of physic 1999.2.2.2 Order-Disorder TheoryThe orde r-Disorder mechanism is first suggested by Hoffman (Hoffman 1972) which obeserved the monodispersed supension at a lower place shear generate different patterns at critical shear rate ( before and after). According to this theory, when the suspension is sheared, particles is ordered in the specific formation ( hexangular or pentagonal) of jammed layers parallel to the plane of shear. After a crtical stress is reached, the instabilities in the formation of jammed layers become greater and particles are out of the formation. Then, these particles collide and jammed to each other and produce in the hold up of viscosity.An example of these pattern can be seen in figure 4 Hoffman monitored the monodispersed suspension under shear and showed that figure 4(A) corresponds to the order formation of the packed layers while figure 4(B) is disorder or random formation of the packed layers after critical shear stress is reached.The illustration of the phenomenon for the order- disorder form ation of the packed layers that suggested by Hoffman can be seen in figure 5. those formation is captured by the Hoffman by using a simple shear in figure 4 (A) is same formation in the figure 5 (A). Hoffman predicted that, those formation occur due to the strong surface bonding in the monodisperse suspension which normally reffered to the total heat and van der waals bond. In figure 5 (B), the disorder formation occurs when sample shear above critical shear stress. Particle are collide and jammed each other and produce in rise of viscosity due to the agglomeration of the particles.2.2.3 Introduction Liquid-Solid Transition (LST)In this paper, a new concept theoretical onset transition of STF will be proposed. The main ideas of this theoretical concept are the macrostructure of the fluid are changes during onset transition from liquid state to the solid or gel state, and liquid- solid transition state which is normally involving the relaxation state (). The transition also can be s tate as semi-solid transition at the critical shear rate. This paper, also will be investigated the formation of the transition by using colloidal particles which are stabilize by using two system, steric and electrostatic repulsion system.LST involves many such of factors, such as theory of gelation, branching theories, and percolation theories. All the theory in LST are closely related to the formation of the macrostructure, whether effect on the temperature surrounding or over time.2.2.3.1 Theory of GelationThe LST of polymers is also technically important since it occurs in nearly all of the common fabrication processes. Examples are injection molding of semi-crystalline polymers (where the surface grapheme of the finished parts may be affected by gelation shear thickening fluid (STF) and touch on of crosslinking polymers. Therefore, the onset transition for STF can be detected by using LST.There are several(prenominal) theories in gelation are normally used in LST. First is b ranching theories and second is percolation theory. The onset transition are very important to the STF for comparison with the hydrocluster formation theories and order disorder theory and proposed new theoretical idea for the rheological behavior due to the factors affecting the performance of STF such as molecular(a)(a) weight dependence, volume fraction dependence and particle particle interaction dependence. Those all factors which affecting the performance of STF had been discussed in previous sub-chapter.2.2.4 Description of the Phenomena for Shear Thickening Fluid (STF)Basically, the phenomenon of STF is investigated by using a hole of parameter in the last two decades. Volume fraction, particle porosity and interparticle interaction dependence is a major parameters for STF. In this paper, molecular weight of carrier fluid is added in the STFs parameter, in order to increase the potential parameter for the STFs phenomenon.2.2.4.1 Volume Fraction habituationVolume fraction factor is the main parameter in the shear thickening fluid STF. In general, a solid or hard particle which is suspended in the carrier fluid such as ethylene glycol, polyethylene glycol or other carrier fluid which are aqueous in nature or non-aqueous in nature can exhibit shear thickening behavior at the minimal range of volume fraction in between 30% to 49%. Above 50% of volume fraction, the rheological shear thickening behavior can be measured at lower shear rate but it depending on the complex viscosity of the suspension which is it is related to another parameters like particle size and porosity. Meaning, surface area and aspect ratio of the particle are greater influenced on the final viscosity of the STF.One parameter that has a huge effect on the critical shear rate is the volume fraction. At low volume fractions (below 0.5), shear thickening is either less dramatic or not significant Characterization of Shear-Thickening Fluid-Filled suds system for Use in Energy Absorptio n Devices, Jose 2004.Wagner and his team also claims, colloidal silica ( 14nm) which is suspended in the polyethylene glycol, less than or 30% volume fraction of STF will producing less or no significant of thickening behavior either at low shear rate or higher. Raghavan and khan which studying the rheological behavior of fumed silica suspended in low molecular weight polypropylene glycol claim, non-flocculated suspension exhibit shear thickening at 10% w/w under steady flow and strain-thickening under oscillatory shear. Strain-thickening refer to the abrupt increase in the complex modulus complex viscosity.Fumed silica generally known has higher agglomeration size up to 140 micron. Therefore, volume fraction has less significant affected on the shear thickening behavior. The agglomeration size is the main factor in the Raghavan and caravanserai studies (figure 2.2.4).The results of Barnes demonstrate that at volume fractions in the range of 50 %, the shear thickening behavior is judge and predictable. In addition, theoretical analysis of the maximum volume fraction of monodispersed suspensions predicts this value is max=0.605, where this value corresponds to, the volume fraction for a cubically stacked hexagonal packing (Boersma et al. 1989).2.2.4.2 Molecular Weight of the Carrier Fluid DependenceMolecular weight of the carrier fluid is a new parameter in the STF. Wagner and his team account that the viscosity of the carrier fluid is important to predict the onset transition from shear thinning to the shear thickening behavior in the STF. A difficulty occurs from getting exacts experimental measurement of the effect of carrier fluids due to the reality that changing the carrier fluid affects the interparticles interaction. In this paper, by monitoring the zeta potential of the carrier fluid, those two effects (molecular weight dependence and Particle-Particle Interaction Dependence) can be separated.The onset transition of STF will be a main indicator for this parameter neither the suspension are flocculated or deflocculated. The idea of used difference molecular weight is cames from colloidal suspension which prepared by raghvan, in his experiment polypropylene glycol (PPG) as a main carrier fluid. He are experimental the effect of the rheological behavior for fumed silica suspended in PPG at lower concentration (mass fraction), and showed the STF behavior at low yield stress (figure 6). The experiment by raghvan is difference from wagner and barnes, which used colloidal particle from Nissan Chemicals (MP4540) and suspended in PEG 200 at high concentration for exhibit shear thicknening behavior (figure 6).Therefore, when turnable fumed silica particle into colloidal fumed silica via steric and electrostatic repulsion system, suspended it in the different molecular weight of carrier fluid at various particle loadings, believed, the suspension will exhibited shear thickening behavior at low yield stress.2.2.4.3 Particle-Particle Inter action DependenceInterparticles interactions are very important in determining the shear thickening behavior of a suspension. Flocculated suspension will not exhibit shear thickening (Barnes 1989), but instead they will show shear thinning, as shown in figure 7.Basically, the flow behavior of a suspension is extremely affected by interparticle interaction. These phenomenons also refer to the final condition which refers to the pH value of a suspension. Therefore in table 1, the Floc sizes are monitored due to the effect of pH value, electrolytes, and polymer on a kaolin suspension. Because of flocculation is expected to begin at lower pH values, namely edge to face that kaolin is positively charged and de-flocculation at higher pH values it carries a net negative charge on the surface. (Nongkhran Chaiwong 2008).The flocculation of kaolin depended on pH, electrolytes and polymers flocculants. Floc size and floc strength increased with increasing of cation valency in the electrolytes and increasing of molecular weight in the polymers (Nongkhran Chaiwong 2008).The information that gathered from table 1 is important for the colloidal suspension