Polymer blends morphology

Semi-crystalline polymers often manifest a lamellar morphology consisting of stacks of laminar crystals with a characteristic thickness of 1, intercalated by an amorphous region represented by a length scale, l. Polymer blends that consists 

The different characteristic length scales so defined in a semi-ctystalline polymer or a blend consisting of at least one crystallizable component are thus accessible in X-ray scattering experiments and are probed by varying the scattering angle (SAXS or WAXD) that depends on the available sample to detector distance of the instrumental set-up. 

---

P. M. Subramaniam, Polymer Blends Morphology and Solvent Barriers, ACS, Washington (1990). 

Huneault, M. A., Shi, Z. H., and Utracki, L. A., Development of polymer blend morphology during compounding in a twin-screw extruder. Part IV A new computational model with coalescence. Polym. Eng. Sci. 35(1), 115-127 (1995). 

Electron microscopy, 16 464, 487-495 history of, 16 487-488 in polymer blend morphology determination, 20 339-340 of PVC particles, 25 658-659 of silica, 22 371-372 in surface and interface imaging, 24 75-80... 

Rusu D (1997) In-situ study of immiscible polymer blends morphology under simple shear PhD thesis Ecole des Mines de Paris, Sophia Antipolis... 

Blend systems are introduced by a timely review by Donald Paul and Joel Barlow focused on blend technology. This review includes a discussion of the increasingly important topic of polymer miscibility in engineering thermoplastics. The 15 papers that follow present a variety of approaches to polymer-blend morphology study, fracture and defor-... 

Hobbs SY, Dekkers MEJ and Watkins VH (1988) Effect of interfacial forces on polymer blend morphologies. Polymer 29 1598-602. 

Gramespacher H and Meissner J (1997) Melt elongation and recovery of polymer blends, morphology, and influence of interfacial tension. J Rheol 41 27-44. 

Frost J. M., Cheyitis F., Tuladhar S. M. and Nelson J. (2006), Influence of polymer-blend morphology on charge transport and photocurrent generation in donor-acceptor polymer blends , Lett. 6, 1674-1681. 

SUBRAMANIAN Polymer Blends Morphology and Solvent Barriers... 

Scheme 1 Different possible donor-acceptor active layer morphologies in OPV devices. The left drawing depicts a macrophase separated polymer blend morphology with undefined domains. In the middle and at the right, schematic active layer morphologies of disordered and vertically aligned microphase separated block copolymer thin films are shown. Dark and light grey domains correspond to the donor and the acceptor phase, respectively...

Table 7.6. Studies of flow field effects on polymer blends morphology...

In the first part of the chapter several methods used to observe morphology of polymer blends are presented. Various optical microscopic methods are reviewed, including such modem techniques as photon tunneling microscopy (PTM), scanning near-field optical microscopy (SNOM), phase measurement interference microscopy (PMIM), surface plasmon microscopy (SPM) and optical waveguide microscopy (OWM). Many of these methods have been developed to study surfaces and thin films. However, they can also be applied to polymer blend morphology. 

There are several developments in OM to overcome the classical limits. So far, they are mostly applied for the analysis of surface and thin film of polymers. However, they could be equally well used for smdies of polymer blend morphology. 

As the molecular size of most gases is much smaller than any scale of structure expected in polymer blend morphology, diffusion and permeability of gases can be employed to determine the phase behavior of a polymer blend. Therefore, the study of transport phenomena in blends would be motivated not only by the requirements of producing improved barrier materials but also by the continuous interest in the nature and characterization of polymer blend morphology. 

Process parameters can play a significant role in controlling the polymer blend morphology. Smaller domains and thus smaller characteristic lengths would be expected at higher spin speeds, because of the shorter times available for the phases to coalesce. Figure 10.7 shows the FESEM images of... 

M.A. Huneault, M.F. Champagne, A. Luciani, J.-F. Hetu, L.A. Utracki, Generation of Polymer Blends Morphology (Polymer Processing Society, Stuttgart, 1995a)... 

---