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1.
Ultra-high-molecular-weight polyethylene (UHMWPE) – carbon black (CB) blends were prepared by gelation/ crystallization from
PE dilute solutions containing CB particles. The UHMWPE/CB composition chosen were 1/0.15, 1/0.25, 1/0.5, 1/0.75, 1/1, 1/3,
1/5, and 1/9, etc. The cross-linking of PE chains was performed by chemical reaction of dicumyl-peroxide at 160 °C. X-ray diffraction patterns indicate that the crystallinity of PE within the blends decreased drastically through the chemical
reaction at high temperature. The sample preparation method by gelation/crystallization provided the UHMWPE–CB system with
various CB contents up to 90% and the conductivities for the resultant specimens were in the range from 10-9 to 1 Ω-1 cm-1 corresponding to the electric conductivity range of semiconductors. The blends assured thermal stability of electric conductivity
by cross-linking of PE chains, although the mechanical property such as the storage and loss moduli were very sensitive to
temperature. The conductivity of the blends with CB content ≥20% were almost independent of temperature up to 220 °C and the values in the heating and cooling processes were almost the same. On the other hand, for the UHMWPE–CB blends with
13% CB content corresponding to the critical one, temperature dependence of electric resistivity showed positive temperature
coefficient (PTC) effect. The PTC intensities for non-cross-linked and cross-linked materials were lower than that of the
corresponding low-molecular-weight-polyethylene (LMWPE)–CB blend but the maximum peak appeared at 160 °C which is higher than the peak temperature of LMWPE–CB blend.
Received: 10 December 1997 Accepted: 9 April 1998 相似文献
2.
Ru Chen Yuezhen Bin Yumiko Nakano Naoko Kurata Masaru Matsuo 《Colloid and polymer science》2010,288(3):307-316
In an attempt to improve the mechanical property of polyethylene composite at high temperature, crosslinking of ultrahigh-molecular-weight
polyethylene (UHMWPE) and carbon fiber (CF) blends was carried out by using dicumyl peroxide (DCP). The specimens were prepared
by gelation/crystallization from solutions. The effect of chemical crosslinking on mechanical and electrical properties of
UHMWPE/CF blends with composition of 1/0, 1/0.25, and 1/1 (w/w) were investigated in detail. Electrical conductivity and thermal mechanical properties of the blends with the 1/1 composition
were greatly improved by incorporation of enough content of CF and adequate crosslinking network formation. Surprisingly,
the Young’s modulus of the 1/1 blend reached 20 GPa at room temperature (20 °C). On the other hand, heat treatment at 135 °C
played an important role for obtaining a high PTC effect for the UHMWPE-CF blend in which the PTC intensity reached 107. 相似文献
3.
Mário A. P. Nunes Hélder Vila-Real Pedro C. B. Fernandes Maria H. L. Ribeiro 《Applied biochemistry and biotechnology》2010,160(7):2129-2147
A synthetic polymer, polyvinyl alcohol (PVA), a cheap and nontoxic synthetic polymer to organism, has been ascribed for biocatalyst
immobilization. In this work PVA–alginate beads were developed with thermal, mechanical, and chemical stability to high temperatures
(<80 °C). The combination of alginate and bead treatment with sodium sulfate not only prevented agglomeration but produced
beads of high gel strength and conferred enzyme protection from inactivation by boric acid. Naringinase from Penicillium decumbens was immobilized in PVA (10%)–alginate beads with three different sizes (1–3 mm), at three different alginate concentrations
(0.2–1.0%), and these features were investigated in terms of swelling ratio within the beads, enzyme activity, and immobilization
yield during hydrolysis of naringin. The pH and temperature optimum were 4.0 and 70 °C for the PVA–alginate-immobilized naringinase.
The highest naringinase activity yield in PVA (10%)–alginate (1%) beads of 2 mm was 80%, at pH 4.0 and 70 °C. The Michaelis
constant (K
Mapp) and the maximum reaction velocity (V
maxapp) were evaluated for both free (K
Mapp = 0.233 mM; V
maxapp = 0.13 mM min−1) and immobilized naringinase (K
Mapp = 0.349 mM; V
maxapp = 0.08 mM min−1). The residual activity of the immobilized enzyme was followed in eight consecutive batch runs with a retention activity
of 70%. After 6 weeks, upon storage in acetate buffer pH 4 at 4 °C, the immobilized biocatalyst retained 90% of the initial
activity. These promising results are illustrative of the potential of this immobilization strategy for the system evaluated
and suggest that its application may be effectively performed for the entrapment of other biocatalysts. 相似文献
4.
Masuhiro Tsukada Giuliano Freddi John S. Crighton 《Journal of Polymer Science.Polymer Physics》1994,32(2):243-248
The structure and compatibility of poly(vinyl alcohol)-silk fibroin (PVA/SF) blend films were analyzed by differential scanning calorimetry (DSC), thermomechanical (TMA) and thermogravimetric (TGA) analysis, x-ray diffractometry, and scanning (SEM) and transmission (TEM) electron microscopy. DSC curves of PVA/SF blend films showed a major endothermic peak at 220°C, along with a peak at 280°C. These endotherms were assigned to the thermal decomposition of the ordered PVA elements and to the thermal degradation of silk fibroin, respectively. The PVA/SF blends behaved in a manner intermediate to the pure components, as suggested by both contraction expansion and sample weight retention properties recorded by TMA and TGA measurements. The IR absorption spectra of the blends were identified as purely a composite of the absorption bands characteristic of both PVA and SF pure polymers. The X-ray diffraction patterns of PVA/SF blends showed overlapping spacing due to PVA and SF. A dispersed phase formed by spherical particles of 3–7 μm diameter was observed by SEM and TEM. All these findings suggest that PVA and SF are incompatible. © 1994 John Wiley & Sons, Inc. 相似文献
5.
Li-Ting Lee Eamor M. Woo Wei-Ting Chen Ling Chang Kai-Cheng Yen 《Colloid and polymer science》2010,288(4):439-448
Miscibility with a linear T
g–composition relationship was proven for blend of poly(butylene adipate-co-butylene terephthalate) [P(BA-co-BT)] with poly(4-vinyl
phenol) (PVPh). In comparison to the blends of PBA/PVPh and poly(butylene terephthalate) (PBT)/PVPh, the Kwei’s T
g model fitting on data for the P(BA-co-BT)/PVPh blend yields a q value between those for the PBA/PVPh and PBT/PVPh blends. The q values suggest that the interaction strength in the P(BA-co-BT)/PVPh blend is not as strong as that in the PBT/PVPh blend.
Upon mixing the PVPh into the immiscible blend of PBA and PBT, the ternary PBA/PBT/PVPh blends only exhibits partial miscibility.
Full-scale ternary miscibility in whole compositions is not possible owing to the significant ∆χ effect (χ
ij
– χ
ik
). The wavenumber shifts of the hydroxyl IR absorbance band indicates that the H-bonding strength is in decreasing order—PBT/PVPh
> P(BA-co-BT)/PVPh > PBA/PVPh—and shows that the BA segment in the copolymer tends to defray interactions between P(BA-co-BT)
and PVPh in blends. 相似文献
6.
Kyu-Oh Kim Yun-A Seo Byoung-Suhk Kim Kee-Jong Yoon Myung-Seob Khil Hak-Yong Kim Ick-Soo Kim 《Colloid and polymer science》2011,289(8):863-870
We report solution properties of the blend solutions of poly(vinyl alcohol) (PVA) and poly(ethylene glycol) (PEG)–POSS telechelic
and its corresponding hybrid nanofibers prepared by electrospinning. The morphologies, microstructures, and wettability of
the resulting PVA/PEG3.4k–POSS hybrid nanofibers are studied. The morphologies of the resultant PVA/PEG3.4k–POSS nanofibers
are regular with the fiber diameter ranging from 610 ± 110 to 810 ± 280 nm. When the content of PEG3.4k–POSS telechelic increases
above 20 wt.%, the beaded fiber morphologies are observed due to severe aggregations of the PEG3.4k–POSS telechelics as well
as increased viscosity at higher concentration. In addition, the solution properties of pure PEG3.4k–POSS telechelic solution
(ca. 3–5 wt.%) and PVA/PEG3.4k–POSS solutions blended with PVA are explored, and found to show the reversible turbid-to-transparent
transition behavior with respect to the solution temperature. Water contact angle measurement of the PVA/PEG3.4k–POSS nanofiber
membranes demonstrates an enhanced hydrophobic nature due to the incorporated POSS moieties. 相似文献
7.
Kariman M. El Salmawi 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(5):541-545
Crosslinked polyvinyl alcohol (PVA) and chitosan polymer blends have been prepared by using gamma irradiation. Chitosan was used in the blends to prevent microbiological growth, such as bacteria and fungi on the polymer. The physical properties of the blend, such as gelation, water absorption, and mechanical properties were examined to evaluate the possibility of its application for wound dressing. A mixture of PVA/chitosan, with different ratios, were exposed to gamma irradiation doses of 20, 30, 50 KGy, to evaluate the effect of irradiation dose on the physical properties of the blend. It was found that the gel fraction increases with increasing irradiation dose and PVA concentration in the blend. Swelling percent increased as the composition of chitosan increased in the blend. The PVA/chitosan blend has a water content in the range between 40% and 60% and water absorption between 60% and 100%. The water vapor transmission rate value (WVRT) of the PVA/chitosan blend varies between 50% and 70%. The examination of the microbe penetration shows that the prepared blend can be considered as a good barrier against microbes. Thus, the PVA/chitosan blend showed satisfactory properties for use as a wound dressing. 相似文献
8.
Phase behavior and crystal morphology in poly(ethylene succinate) biodegradably modified with tannin
Siti Nurkhamidah Eamor M. Woo I-Han Huang Chean C. Su 《Colloid and polymer science》2011,289(14):1563-1578
Specific interactions, growth kinetics, and dendritic morphology in poly(ethylene succinate) (PESu) biodegradably modified
with various contents of tannic acid (TA) were characterized using differential scanning analysis, Fourier-transform infrared
(FTIR) spectroscopy, polarized-light optical microscopy, and atomic force microscopy. Strong interactions and highly retarded
growth between PESu and a macromolecular ester with polyphenol groups, TA, interaction-induced highly retarded growth rates
for the PESu/TA (80:20) composition are proven to lead to single-crystal-like dendrites when crystallized at high crystallization
temperature (T
c). At T
c = 70 °C, the growth rate for neat PESu is 12 μm/min while it is dramatically depressed to one tenth-fold at 1.5 μm/min with
20 wt.% TA in the blend. Strong specific interactions between the carbonyl group of polyesters and the phenolic hydroxyl group
of TA are confirmed by (1) the blend’s glass transition temperature (T
g)–composition relationship exhibits a sigmoidal curve, well fitted by the Kwei T
g model for miscible blends with large negative q = −90; (2) thermal analysis on crystal melting revealed an interaction parameter χ = −0.64 between PESu and TA; and (3) IR peak shifting analyzed using two-dimensional FTIR technique. A comparative blend
of another polyester poly(hexamethylene sebacate) with TA, lacking the specific interactions, does not exhibit such single
crystals upon similar melt crystallization. 相似文献
9.
We studied the adsorption of two neutral polymers [poly(vinyl pyrrolidone) and poly(vinyl alcohol) (PVA)] on negatively charged
liposomes composed of 25:2:3 (molar ratio) soy lecithin/dicetyl phosphate/cholesterol.The liposomes were prepared in buffered
solution at pH 7.4 and were mixed with the solution of the polymers in the desired polymer/lipid ratios. Adsorption was measured
by determination of the equilibrium bulk concentration of the polymer. Protamine hydrochloride was used to aggregate the liposomes
with polymers adsorbed on their surface and to facilitate their separation from the equilibrium bulk solution. In the case
of PVA, quantitative adsorption measurements with a specific reagent were possible. Adsorption isotherms were recorded at
25 ± 0.2 °C. It was concluded that adsorbed and nonadsorbed PVA molecules are in equilibrium even at low polymer/lipide ratios.
The results were confirmed by dynamic laser light scattering, X-ray diffraction and thermal activity monitoring experiments.
Received: 13 October 2000 Accepted: 8 March 2001 相似文献
10.
The copolymers of methyl methacrylate (MMA) (or styrene (ST))/stearyl methacrylate (SMA) obtained from miniemulsion polymerization
were prepared and characterized. All the miniemulsions showed satisfactory colloidal stability upon aging due to the effectively
retarded Ostwald ripening by the reactive costabilizer SMA. In subsequent miniemulsion copolymerizations, monomer droplet
nucleation predominated in the particle formation process, but homogeneous nucleation could not be ruled out even at such
high levels of SMA (20–50 wt.%). The contact angle first increased rapidly and then leveled off when the SMA content increased
from 20 to 50 wt.% for both the copolymers of MMA/SMA and ST/SMA. At constant level of SMA, the copolymer of MMA/SMA with
a less hydrophobic composition showed a larger contact angle compared to the ST/SMA counterpart. The contact angle (103 ± 1°)
of the copolymer MMA/SMA (50/50 w/w) was comparable to that (104°) of PSMA. A schematic model was proposed to explain the experimental results. 相似文献
11.
The fungicide triadimenol consists of a mixture of two diastereoisomers. Diastereoisomer A (1RS,2SR) could be obtained from the mixture by fractionated crystallization from ethanol/water and toluene, successively, whereas
diastereoisomer B (1RS,2RS) could be separated by column chromatography on a silica gel column using ethylacetate as eluent. Four different crystal
forms of diastereoisomer A could be derived. The modifications were characterized by means of thermal analysis (thermomicroscopy,
DSC), FTIR-spectroscopy, FT-Raman-spectroscopy and powder X-ray diffraction, as well as pycnometry. The thermodynamic relationships
are illustrated in a semischematic energy/temperature-diagram which provides information about the relative thermodynamic
stabilities and physical properties of the four crystal forms. Mod. II (m.p. 132 °C, ΔHf 33.1±0.2 kJ mol−1, density 1.271±0.001 g cm−3) was obtained from toluene after the separation of diastereoisomer A and is enantiotropically related to mod. I (m.p. 138 °C,
ΔHf 32.0 ± 0.2 kJ mol−1, density 1.243±0.001 g cm−3). The transition point of mod. II with mod. I was determined between 30 and 40 °C, which means that mod. II is thermodynamically
stable at ambient conditions. Mod. III (m.p. 112 °C, ΔHf 25.1±0.5 kJ mol−1) and mod. IV were obtained from the melt. Furthermore, the phase diagrams of the binary systems of diastereoisomer B and
the four modifications of diastereoisomer A were calculated by means of the experimentally obtained thermodynamical data.
Received September 30, 1999. Revision July 30, 2000. 相似文献
12.
Chunguang Wang Zishou Zhang Kancheng Mai 《Journal of Thermal Analysis and Calorimetry》2011,106(3):895-903
β-nucleated PP/PET blends were prepared using nano-CaCO3 supported β-nucleating agent (β-NA), PP as matrix, and PET as dispersion phase. The effects of preparation methods, PET content, and melting temperature
on the non-isothermal crystallization behavior and the melting characteristic and polymorphic composition of PP in the blends
were investigated by differential scanning calorimeter (DSC) and wide angle X-ray diffraction (WAXD). The results indicated
that the PP crystallized predominantly in β-modification in the presence of β-NA. However, efficiency of β-NA for PP crystallization decreased with addition of PET and increasing PET contents. The β-nucleation of β-NA for PP crystallization in the blends was dependant on the preparation methods. The high β-nucleation and high β-PP content were obtained for PP/PET blend prepared at the temperature of 265 °C and added the β-NA into the blend at the temperature of 180 °C. However, the addition of β-PP or β-NA into blends at 265 °C decreased the β-nucleation, and no β-PP was formed because the β-NA mainly dispersed on the PET dispersion phase or at the interface between PP and PET. 相似文献
13.
The mechanical and electrical properties of solution-processed [or gel-spun] blends of poly(3-octylthiophene) and ultrahigh molecular weight polyethylene are discussed. Tensile drawing at elevated temperatures of the phase-separated blends resulted in significant improvements of the mechanical properties, in comparison with those of the neat conducting polymer, with values of the Young's modulus reaching > 40 GPa and tensile strengths in excess of 2 GPa. Doping of the undrawn polyblend fibers with iodine vapor or FeCl3 resulted in materials of useful levels of electrical conductivity covering the full range of 10?15 to 10 S/cm. A distinct percolation threshold for electrical conductivity was not observed, even at poly(3-octylthiophene) concentrations as low as 0.5 w/w %; the electrical conductivity of the latter blend, after doping with iodine vapor, was 8 × 10?8 S/cm. 相似文献
14.
Won-Ill Cha Suong-Hyu Hyon Yoshito Ikada 《Journal of Polymer Science.Polymer Physics》1994,32(2):297-304
Gel spinning of poly(vinyl alcohol) (PVA) was attempted from the PVA dope prepared from the mixture of dimethyl sulfoxide (DMSO) and water. The DMSO/H2O = 80/20 (w/w) mixture and methanol were found to be the best solvent for the spinning dope and the coagulant, respectively, to give PVA fiber with the highest drawability. PVA fiber with the highest strength and Young's modulus were obtained from the undrawn gel fibers when subjected to hot two-stage drawing under conditions such as to produce maximum drawability. Furthermore, higher draw ratios of PVA fiber were attained at 6 wt % dope by lowering the coagulating temperature of methanol. In the present work, the highest tensile strength (2.8 GPa) and the highest Young's modulus (64 GPa) were realized, when the spinning dope was prepared from PVA with DP of 5,000 and the DMSO/H2O (80/20) mixed solvent to have the PVA concentration of 6 wt %, the coagulating temperature of methanol was ?20°C, and the two-stage drawing was carried out at 160 (first) and 200°C (second). The PVA fiber prepared under this gel spinning condition could be elongated to 45 times draw ratio. The very high drawability of PVA fibers obtained from the DMSO/H2O (80/20) mixture dope was ascribed to the ability of the DMSO/H2O mixture to promote gelation. © 1994 John Wiley & Sons, Inc. 相似文献
15.
D. Rana K. Bag S. N. Bhattacharyya B. M. Mandal 《Journal of Polymer Science.Polymer Physics》2000,38(3):369-375
A miscible homopolymer–copolymer pair viz., poly(ethyl methacrylate) (PEMA)–poly(styrene‐co‐butyl acrylate) (SBA) is reported. The miscibility has been studied using differential scanning calorimetry. While 1 : 1 (w/w) blends with SBA containing 23 and 34 wt % styrene (ST) become miscible only above 225 and 185 °C respectively indicating existence of UCST, those with SBA containing 63 wt % ST is miscible at the lowest mixing temperature (i.e., Tg's) but become immiscible when heated at ca 250 °C indicating the existence of LCST. Miscibility for blends with SBA of still higher ST content could not be determined by this method because of the closeness of the Tg's of the components. The miscibility window at 230 °C refers to the two copolymer compositions of which one with the lower ST content is near the UCST, while the other with the higher ST content is near the LCST. Using these compositions and the mean field theory binary interaction parameters between the monomer residues have been calculated. The values are χST‐BA = 0.087 and χEMA‐BA = 0.013 at 230 °C. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 369–375, 2000 相似文献
16.
The differential orientation of polymer chains has been measured in polystyrene (PS)/poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) compatible blends. Density measurements are reported as a function of binary blend composition at 23°C. Drawing was performed by solid-state coextrusion. PS/PPO blend compositions of 90/10 and 75/25 were drawn within sandwiches of polyethylene at 145°C and isotactic polypropylene at 155°C, i.e. at ca. 25°C above the glass transition temperatures of the two blends. The change in Fourier-transform infrared dichroisms on drawing these blends was measured at 906 and 1190 cm?1, corresponding to predominantly PS and PPO, respectively. The orientation of PS and PPO was observed as a function of draw ratio λ in the range 1–5; orientations increased with λ for both PS and PPO in both blends but to different degrees. Both polymers decreased in orientation with increasing PPO content. Annealing with fixed ends showed that the PPO chains disorient more slowly than those of PS. All binary systems were found to be amorphous and compatible. 相似文献
17.
Markéta Julinová Jan Kupec Jaromír Hoffmann Tomáš Vojtek Peter Bugaj 《Polymer Degradation and Stability》2010,95(2):225-1540
The objective of this work was to study the biodegradation of blow-moulded films of poly(vinyl alcohol) (PVA)/protein hydrolysate (PH) which contain biodegradation inductors of the starch (S) and lignin (LI) types. These increase the biodegradation rate of PVA while preserving or improving the technical and usage properties of blends. The aim of the work was to reach the maximum breakdown rate so that rapid disintegration of PVA could take place at a wastewater treatment plant. The biological material chosen was activated sludge from a municipal wastewater treatment plant. Preparation of the blends required that a plasticiser be used, in this case glycerol (G). This allowed for successful processing but prolonged the lag phase of PVA breakdown as well as reducing its final biodegradation percentage. The influence of G, in this respect, was not affected by incorporating PH. S and LI reduced the influence of the plasticiser but caused a breakdown rate comparable to PVA itself. Contrarily, after adapting biomass to PVA, applying G produced a PVA breakdown rate three times greater, albeit with a lag phase prolonged fivefold. However, due to the duration of breakdown (the period above the retention time of wastewater during activation), this effect was not positive. The addition of PH to the blends mentioned did not exhibit any clear favourable influence. Adding S resulted in a shorter lag phase, in addition to which the degradation rate increased by approximately 1.5 times. Combining LI and S distinctly accelerated the degradation of a blend, although a disadvantage of doing so is an incomplete breakdown of the substrate, which lowers the final biodegradation percentage. Therefore, an eventual compromise was arrived at, this being a blend of PVA/G PH S. Its breakdown time is half that of pure PVA, and the films produced, from a mechanical standpoint, are more convenient. 相似文献
18.
The effect of montmorillonite clay (MMT) and/or chain extender (CE) on rheological, morphological and biodegradation properties of PLA/PBAT blend was investigated. The biodegradation behavior was evaluated by CO2 evolution in soil burial. CE incorporation resulted in an increase in the complex viscosity of PLA/PBAT blends, an increase in PLA crystallinity and a decrease in the dispersed phase diameter. MMT incorporation resulted in an increase in the complex viscosity, more pronounced shear-thinning behavior and a decrease in the dispersed phase diameter. CE incorporation resulted in a slight effect in the rheological properties of PLA/PBAT blend in the presence of MMT. Unfilled PLA/PBAT blend presented the highest amount of evolved CO2, and the micrographs indicated that degradation tends to occur on the surface. MMT delayed biodegradation of PLA/PBAT blends even although their surfaces presented some cracks and holes in a few localized regions. PLA/PBAT + CE blend presented the lowest amount of evolved CO2. 相似文献
19.
W. Lyoo J. Yeum H. Ghim J. Park S. Lee J. Kim D. Shin J. Lee 《Colloid and polymer science》2003,281(5):416-422
To precisely identify the effect of the molecular weight of syndiotactic poly(vinyl alcohol) (s-PVA) on the water stability of a s-PVA/iodine complex film, we prepared four s-PVAs with similar syndiotactic diad (s-diad) contents of about 63% and with different number-average degrees of polymerization, Pn, of 900, 6,000, 10,000, and 17,000, respectively. The desorption behavior of iodine in the s-PVA/iodine complex film in water was investigated in relation to the solubility of s-PVA in water. The degree of solubility of a s-PVA film having different Pn in water at 80 °C was limited to about 0.3-10%, whereas the degrees of solubility of atactic PVA films with Pn of 6,000 and 10,000 were 100% at the same conditions. The degree of iodine desorption of the complex film decreased with increasing Pn of s-PVA. Especially, the degree of iodine desorption of a PVA drawn film having Pn of 17,000 was limited to 2%, regardless of soaking temperature from 40 to 80 °C. The desorption of iodine in water was strongly affected by the dissolution of PVA. In addition, the degree of iodine desorption of the drawn s-PVA/iodine film was larger than that of the undrawn one. 相似文献
20.
Miscibility and morphology of poly(ethylene 2,6-naphthalate)/poly(trimethylene terephthalate)/poly(ether imide) (PEN/PTT/PEI)
blends were investigated by using a differential scanning calorimeter (DSC), optical microscopy (OM), wide-angle X-ray diffraction
(WAXD), and proton nuclear magnetic resonance (1H-NMR). In the ternary blends, OM and DSC results indicated immiscible properties for polyester-rich compositions of PEN/PTT/PEI
blends, but all compositions of the ternary blends were phase homogeneous after heat treatment at 300 °C for more than 30 min.
An amorphous blend with a single T
g was obtained in the final state, when samples were annealed at 300 °C. Experimental results from 1H-NMR identified the production of PEN/PTT copolymers by so-called “transesterification”. The influence of transesterification
on the behaviors of glass transition and crystallization was discussed in detail. Study results identified that a random copolymer
promoted the miscibility of the ternary blends. The critical block lengths for both PEN and PTT hindered the formation of
crystals in the ternary blends. Finally, the transesterification product of PEN/PTT blends, ENTT, was blended with PEI. The
results for DSC and OM demonstrated the miscibility of the ENTT/PEI blends. 相似文献