Rheology Complex Fluids Molecular Rheology Lab Department of

Rheology Complex Fluids & Molecular Rheology Lab. , Department of Chemical Engineering 中央大學化材系講稿 10/28/2011

什 麼 是 流 變 (Rheology)? o Rheology is the science of fluids. More specifically, the study of Non-Newtonian Fluids Newton’s law of viscosity 牛頓流體 - 水、有機小分子溶劑等 o 流體 黏度η為定值 非牛頓流體 - 高分子溶液、膠體等 Small molecule ● Macromolecule Deformable 黏度不為定值 (尤其在快速流場下)

非 牛 頓 流 體 的 特 徵 o 非牛頓黏度 (Non-Newtonian Viscosity) - Shear Thinning Flow curve for non-Newtonian Fluids 牛頓流體 (甘油加水) 非牛頓流體 (高分子溶液)

o 記憶效應 (Memory effects) - Elastic Recoil - Open Syphon Flow

Time-dependent effects (搖變性) Thixotropy behavior Anti-thixotropy behavior A decrease (thixotropy) and increase (anti-thixotropy) of the apparent viscosity with time at a constant rate of shear, followed by a gradual recovery when the motion is stopped The distinction between a thixotropic fluid and a shear thinning fluid: l A thixotropic fluid displays a decrease in viscosity over time at a constant shear rate. l A shear thinning fluid displays decreasing viscosity with increasing shear rate.

o 典型製程之流場強度範圍 Lubrication High-speed coating Rolling Spraying Injection molding Pipe flow Chewing Extrusion Sedimentation Typical viscosity curve of a polyolefin- PP homopolymer, melt flow rate (230 C/2. 16 Kg) of 8 g/10 minat 230 C with indication of the shear rate regions of different conversion techniques. [Reproduced from M. Gahleitner, “Melt rheology of polyolefins”, Prog. Polym. Sci. , 26, 895 (2001). ]

小振幅反覆式剪切流: 黏性與彈性檢定 Exp b: Small-Amplitude Oscillatory Shear Flow Oscillatory shear strain, shear rate, shear stress, and first normal stress difference in small-amplitude oscillatory shear flow

It is customary to rewrite the above equations to display the in-phase and out-of-phase parts of the shear stress Storage modulus Loss modulus Storage and loss moduli, G’ and G”, as functions of frequency ω at a reference temperature of T 0=423 K for the low-density polyethylene melt shown in Fig. 3. 3 -1. The solid curves are calculated from the generalized Maxwell model, Eqs. 5. 2 -13 through 15

流體加 性質 macrorheology microrheology 基本流變性質 the De, Wi numbers 機械量測 本質方程式 closure approximations microscopy/spectroscopy birefringence/dichroism light/ neutron scatterings particle tracking 光學量測 molecular orientation / alignment particle size distribution/ diffusivity micro/mesoscopic structures 分子動力理論 flow pattern monomer mobility, elastic modulus etc. 模流分析 Traditional route Modern (predictive) route n atter p w flo 量子、原子、多尺度計算 物質特性( 化學合成)

Polarizer Analyzer PMT VV and VH polarizations; θ = 30° to 150° Multi-angle dynamic/static light scattering

Morphologies of MEH-PPV Solutions translational internal 1 mg/m. L MEH-PPV/toluene 1 mg/m. L MEH-PPV/chloroform MEH-PPV/toluene MEH-PPV/chloroform

實驗校正: Fig. 1 Comparison of the predicted scattering pattern (the airy function) of a 50 μm pinhole with the experimentally measured one. Fig. 2. Comparison of the form factor predicted by the Mie theory with the experimentally measured one. 應用: SALS之量測角度範圍一般為 1°≦θ≦ 10°，多半作為較大尺度結構解析之用途。其應用範圍可為 高分子材料之混合 (mixing)、分層(demixing)、相變化 (phase changes)、結構破壞 (structure break-up)、與結構整合(structure build-up) 等相關研究。

即時光學—流變系統 示意圖與功能 I. Particle Interactions II. Microstructures III. Molecular Anisotropy

Quartz couette cell (Rheology) 2 -D detection (θ and φ dirs. ) (Flow Light Scattering) Phase-modulated light (Flow Birefringence/Dichroism) CCD camera (Flow SALS) in situ rheo-optical measuring system 實體圖

Parameter-Free Multiscale Simulations ears Co ining gra (5) Dumbbell model & BD simulation (4) Bead-chain model & BD simulation ears Co ining gra (2) Monomer model & CGMD/LD simulation ears Co ining gra (3) Ellipsoid-chain model & MC simulation Shie, S. C. ; Hua, C. C. ; Chen, S. A. , Macromol. Theor. Simul. 2007, 16, 111. Shie, S. C. ; Lee, C. K. ; Hua, C. C. ; Chen, S. A. , Macromol. Theor. Simul. 2010, 19, 179. Lee, C. K. ; Hua, C. C. ; Chen, S. A. , J. Chem. Phys. 2010, 133, 064902. Lee, C. K. ; Hua, C. C. , J. Chem. Phys. 2010, 132, 224904. Lee, C. K. ; Hua, C. C. ; Chen, S. A. , J. Phys. Chem. B 2009, 113, 15937. (1) Atomistic model & MD simulation Lee, C. K. ; Hua, C. C. ; Chen, S. A. , J. Phys. Chem. B 2008, 112, 11479. Hua, C. C. ; Chen, C. L. ; Chang, C. W. ; Lee, C. K. ; Chen, S. A. , J. Rheol. 2005, 49, 641. Lee, C. K. ; Hua, C. C. ; Chen, S. A. , Macromolecules, 2011, 44, 320– 324 Lee, C. K. ; Hua, C. C, Optoelectronics / Book 1, ( In. Tech, ISBN 978 -953 -307 -276 -0) Lee, C. K. ; Hua, C. C. ; Chen, S. A. , (to be submitted). g kin Lin Quantum chemistry calculation

A Software Package under Development for Multiscale simulations Analysis tools Main program Dumbbell model & BD simulation RDF Bead-chain model & BD simulation Structure factor Intensity Monomer model & CGMD/LD simulation Atomistic model & MD simulation Ellipsoid-chain model & MC simulation Back-Mapping techniques The mutiscale simulation package developed at Complex Fluids & Molecular Rheology Laboratory by C. K. Lee, S. C. Shie, and C. C. Hua, in the Department of Chemical Engineering, National Chung Cheng University, Taiwan, R. O. C

Single-Chain Conformations of Conducting Conjugated Polymers from Solution to the Quenching State: A Multiscale Simulation PANI-EB MEH-PPV Vacuum (V) Chloroform (CF) Chlorobenzene (CB) Mixed CF and T vdw + HB + π-π vdw only Mixed CF and CB Toluene (T) Mixed CF and CB

Morphologies and Pair Interactions in Fullerene-Conjugated Oligomer Hybrids Investigated by Atomistic Molecular Dynamics

Links between Molecular dynamics and Quantum chemical calculations Force-field validation: PPV backbone, dihedral angle Energy level diagram for a donor–acceptor heterojunction: Structures refined by semi-empirical (SE) and density functional theory (DFT) Compound 　 (e. V) 　 MEH-PPV LUMO HOMO C 60 PCBM 　 　 SE(PM 3) DFT(B 3 LYP/3 -21 G*) -0. 754 -1. 211 -8. 549 -5. 204 -2. 886 -3. 769 -9. 480 -6. 364 -2. 807 -3. 386 -9. 165 -6. 115 Excitation energies of a single chain MEH-PPV, calculated by ZINDO/S method Chlorobenzene (CB) Mixed Nonane and CB (1: 1) Quantum calculations were carried out using Gaussian 09 software package as provided by the NCHC