Unperturbed dimensions of stereoregular polymers.- Reinforcement of rubber by carbon black.- Transformations of phenolic antioxidants and the role of their products in the long-term properties of polyolefins.

Properties of polymers

By taking the advantage of the unique amphiphilic structure of graphene oxide sheets (GOSs), we develop here a new and effective strategy for compatibilizing immiscible polymer blends. With the incorporation of only 0.5 wt % GOSs into immiscible polyamide/polyphenylene oxide (PA/PPO, 90/10) blends, the droplet diameter of the dispersed minor phase (PPO) is dramatically reduced by more than 1 order of magnitude, indicating a largely improved compatibility in the GOS-filled polymer blends. As a result, the ductility of GOS-compatibilized polymer blends is notably elevated. The compatibilizing effect of GOSs should be due to the fact that GOSs can exhibit strong interactions with both PA and PPO phases, thus minimizing their interfacial tension. Moreover, unlike traditional copolymer compatibilizers, GOSs can also act as reinforcing fillers in polymer blends, thus remarkably enhancing their mechanical strength and thermal stability. Considering the inexpensive sources (graphite powders) and extraordinary pro...

Compatibilization of Immiscible Polymer Blends Using Graphene Oxide Sheets

Grafting of copolymers onto graphene by miniemulsion polymerization for conductive polymer composites: improved electrical conductivity and compatibility induced by interfacial distribution of graphene

The phase behavior and hydrogen bonding in ternary polymer blends of phenolic resin, poly(ethylene oxide) (PEO), and poly(e-caprolactone) (PCL) were investigated by using differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). Although all three binary blends are respective miscible, there exists a closed immiscibility loop in the phase diagram due to the so-called “Δχ” and “ΔK” effects in this hydrogen-bonded ternary polymer system. The interassociation equilibrium constant based on the Painter−Coleman association model between phenolic resin and PEO can be indirectly calculated from the fraction of hydrogen-bonded carbonyl groups. Quantitative analyses show that the hydroxyl−ether interassociation is more favorable than the hydroxyl−carbonyl interassociation at room temperature. The interaction energy density value of BPEO/PCL= −2.85 cal/cm3 was obtained by comparing the theoretically predicted phase diagram with experimental data.

https://ir.nctu.edu.tw:443/bitstream/11536/29097/1/000173023200037.pdf

Phase Behavior and Hydrogen Bonding in Ternary Polymer Blends of Phenolic Resin/Poly(ethylene oxide)/Poly(ε-caprolactone)

https://ir.nctu.edu.tw/bitstream/11536/333/1/A1997XR71000005.pdf

Polymer blends of polyamide-6 (PA6) and poly(phenylene oxide) (PPO) compatibilized by styrene-maleic anhydride (SMA) copolymer

Incompatible polymer blends between polyamide-6 (PA6) and poly(phenylene oxide) (PPO) have been compatibilized in situ by the styrene-glycidyl methacrylate (SG) reactive copolymers. The epoxy functional groups in SG copolymers can react with the PA6 amine and carboxylic endgroups at interface to form various SG-g-PA6 copolymers. These in situ-formed grafted copolymers tend to anchor along interface to function as compatibilizer of the blends. The styrene and the SG segments of the grafted copolymers are miscible (or near miscible) with PPO; whereas the PA6 segments are structurally identical with PA6 phase. The compatibilized blend, depending on quantity of the compatibilizer addition and the glycidyl methacrylate (GMA) content in the SG copolymer, results in smaller phase domain, higher viscosity, and improved mechanical properties. About 5% GMA is the optimum content in SG copolymer that produces the best compatibilization of the blends. This study demonstrates that SG reactive copolymers can be used effectively in compatibilizing polymer blends of PA6 and PPO. © 1996 John Wiley & Sons, Inc.

https://ir.nctu.edu.tw:443/bitstream/11536/1032/1/A1996VF79900021.pdf

Polymer blends of polyamide‐6 and poly(phenylene oxide) compatibilized by styrene‐co‐glycidyl methacrylate

A tetrafunctional epoxy monomer, N,N,N*-N*-tetraglycidyl-4,4*-diaminodi- phenyl methane (TGDDM), has demonstrated to be a highly efficient reactive compati- bilizer in compatibilizing the immiscible and incompatible polymer blends of polyamide- 6 (PA6) and poly(2,6-dimethyl-1,4-phenylene ether) (PPE). This epoxy coupler can react with both PA6 and PPE to form various PA6-co-TGDDM-co-PPE mixed copoly- mers. These interfacially formed PA6-co-TGDDM-co-PPE copolymers tend to anchor along the interface to reduce the interfacial tension and result in finer phase domains and enhanced interfacial adhesion. A simple one-step melt blending has demonstrated to be more efficient in producing a better compatibilized PA6/PPE blend than a two- step sequential blending. The mechanical property improvement of the compatibilized blend over the uncompatibilized counterpart is very drastic, by considering the addition of a very small amount, a few fractions of 1%, of this epoxy coupling agent. q 1998 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 36: 1805-1819, 1998

https://ir.nctu.edu.tw:443/bitstream/11536/32471/1/000074604600002.pdf

Polymer blends of polyamide‐6 (PA6) and poly(phenylene ether) (PPE) compatibilized by a multifunctional epoxy coupler

A commercially available tetrafunctional epoxy monomer was demonstrated to be an effective reactive compatibilizer for blends of poly(ethylene terephthalate) (PET) and polyphenylene ether (PPE). It requires about 10–20% by weight of a conventional reactive compatibilizer to achieve the same level of compatibilization in terms of domain size reduction and mechanical property improvement. This epoxy monomer is able to contact and react with PET and PPE simultaneously during high shear extruder blending to form the desirable PET–epoxy–PPE mixed copolymer. This mixed copolymer contains PET and PPE segments that tend to anchor at the interface to act as an efficient compatibilizer of the PET and PPE blends. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65: 739–753, 1997

https://ir.nctu.edu.tw:443/bitstream/11536/434/1/A1997XG78700012.pdf

Reactive compatibilization of PET and PPE blends by epoxy couplers

The effects of the compatibilizer, styrene maleic anhydride (SMA-8% MA) upon the change of morphology and molecular dynamics of polyamide-6 (PA6) and poly (2,6-dimethyl-1,4-phenylene oxide) (PPO) blends were investigated by means of solid- state NMR techniques. With increasing amounts of SMA, the domains correspond to PA6 and PPO are reduced and the polymer segmental mobility increased. The corre- lation between NMR relaxation time, T1r H , and the bulk mechanical properties provide a molecular level understanding of the modification of molecular dynamics by the compatibilizer (SMA). The correlation shows that the tensile strength is governed mainly by the morphology, but modulated by the PA6 crystallinity, while the tensile elongation and impact strength are closely affected by both the molecular mobility and morphology. The annealing process improved only the tensile strength, but deteriorated tensile elongation and impact strength due to the increase of PA6 crystallinity, which induced phase separation after annealing. This study raised an important point that the polymer mechanical properties are most sensitive to the molecular structure and dynamics take place within the range of 20 A to few hundred A. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 1155-1163, 1999

https://ir.nctu.edu.tw:443/bitstream/11536/31295/1/000079837100010.pdf

Chih-Rong Chiang

Papers

Polymer blends of polyamide-6 (PA6) and poly(phenylene oxide) (PPO) compatibilized by styrene-maleic anhydride (SMA) copolymer

Polymer blends of polyamide‐6 and poly(phenylene oxide) compatibilized by styrene‐co‐glycidyl methacrylate

Polymer blends of polyamide‐6 (PA6) and poly(phenylene ether) (PPE) compatibilized by a multifunctional epoxy coupler

Reactive compatibilization of PET and PPE blends by epoxy couplers

Molecular dynamics and mechanical properties correlations of PA6/PPO blends compatibilized with SMA