Neat PTT Research Articles

Implications of MWCNT reinforcement on the morphology, mechanical and thermal properties of poly-(trimethylene terephthalate)/ polyethylene blend nanocomposites

ABSTRACT The current research offers clear evidence of the reinforcement effect of multi-walled CNTs in the PTT/PE blended system. The combination of PE with PTT decreases the brittleness of PTT and, besides which increases the impact and tensile strength of the blend nanocomposites. By adding 1 wt % MWCNT to the 90PTT/10PE blend system, the impact strength increases to 254% than that of neat PTT. A noticeable fortification of the thermal stability compared to the neat PTT matrix is an added advantage. Among different blend nanocomposites, those with 2 wt. % MWCNT content was proved to be the most favorable concentration showing higher tensile strength, Young’s modulus, and elongation at break. The 90PTT/10PE/2CNT nanocomposites showed a percentage increment of 251% in elongation at break and 129% increment in tensile strength when compared to the 90PTT/10PE blend system. This work provides an efficient alternative way to improve the toughness of an immiscible poly(trimethylene terephthalate)/polyethylene blend system using nanocarbon materials.

Strategy To Improve Printability of Renewable Resource-Based Engineering Plastic Tailored for FDM Applications.

This work features the first-time use of poly(trimethylene terephthalate) (PTT), a biobased engineering thermoplastic, for fused deposition modeling (FDM) applications. Additives such as chain extenders (CEs) and impact modifiers are traditionally used to improve the processability of polymers for injection molding; as a proof of concept for their use in FDM, the same strategies were applied to PTT to improve its printability. The filament processing conditions and printing parameters were optimized to generate complete, warpage-free samples. The blends were characterized through physical, thermal, viscoelastic, and morphological analyses. In the optimal blend (90 wt % PTT, 10 wt % impact modifier, and 0.5 phr CE), the filament diameter was improved by ∼150%, the size of the spherulites significantly decreased to 5% of the ∼26 μm spherulite size found in neat PTT, and the melt flow index decreased to ∼4.7 g/10 min. From this blend, FDM samples with a high impact performance of ∼61 J/m were obtained, which are comparable to other conventional FDM thermoplastics. The ability to print complete and warpage-free samples from this blend suggests a new filament feedstock material for industrial and home-use FDM applications. This paper discusses methods to improve hard-to-print polymers and presents the improved printability of PTT as proof of these methods’ effectiveness.

Morphologically correlated surface characteristics of poly (trimethylene terephthalate)/multiwalled carbon nanotube nanocomposites

In the present work the formation of nano-composites by blending an insulator polymer, poly (trimethylene terephthalate), PTT, with a conducting nano-filler (multiwalled carbon nanotubes, MWCNT) is studied and their surface properties, especially wettability and morphology, are investigated. The PTT/MWCNT nanocomposites show significant enhancements in their non-wettability with the highest water contact angle (θ) of 115° for the PTT/0.5%MWCNT composite, compared to 74° for PTT. Since MWCNT is hydrophobic in nature no correlation of MWCNT content with θ value is seen but a direct correlation of θ with surface roughness data obtained from scanning electron microscopy and atomic force microscopy studies could be made. Various wettability parameters including total surface free energy, work of adhesion, interfacial free energy, spreading coefficient and Girifalco–Good’s interaction parameter were also evaluated for the nanocomposites.Highlights• Effect of conducting filler MWCNT on the surface properties of an insulating polymer PTT was investigated by developing a series of their nano-composites.• Water contact angle θ, wetting parameters like γs, WA, Sc, ϕ could be evaluated and surface roughness of the composites could be found out by SEM and AFM.• Attempt was made to correlate the non-wetting properties of PTT/MWCNT nanocomposites with the MWCNT content and also with the surface morphology/roughness of the composites.• A significant enhancement in hydrophobicity is seen by incorporating just 0.5% MWCNT in PTT with θ value going up to 115° compared to 74° for neat PTT.

Preparation of Maleic Anhydride Grafted Poly(trimethylene terephthalate) (PTT-g-MA) by Reactive Extrusion Processing

Maleic anhydride (MA) grafted with poly(trimethylene terephthalate) (PTT)—abbreviated as PTT-g-MA—can be used as a compatibilizing agent to improve the compatibility and dispersion of nanofillers and a dispersed polymer phase into PTT matrix. This work suggests the preparation of PTT-g-MA using a mixture of PTT, MA, and benzoyl peroxide (BPO) by a reactive extrusion process. PTT-g-MA was characterized to confirm the grafting reaction of maleic anhydride on PTT chains by Fourier transform infrared (FTIR) spectroscopy. Thermal properties (differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA)) and rheological analysis (parallel plates rheology) were used to prove the changes that occurred after the graphitization reaction. The reactive processing route allowed the production of the compatibilizing agent (PTT-g-MA) with good thermal properties and with lower viscosity compared to neat PTT, and this could be an alternative for the compatibilization of polymer blends, as example for PTT/ABS (acrylonitrile butadiene styrene) blends and nanocomposites based on PTT matrix.

Study of Morphological and Mechanical Properties of PBT/PTT Blends and Their Nanocomposites and Their Correlation

Impact modified PBT/PTT blends based nanocomposites having organoclay content varying from 2, 3 and 5 wt% were prepared using corotating twin-screw extruder. Organoclay (Cloisite 30B) was used as nanofiller. Ultra-low-density polyethylene-grafted glycidyl methacrylate (ULDPE-g-GMA) was used as an impact modifier to toughen the polymeric matrices. In all the prepared nanocomposites, the amount of impact modifier (ULDPE-g-GMA) remains constant, i.e., 2 wt%. Izod impact testing showed that only 2 wt% impact modifier (ULDPE-g-GMA) was enough to improve the notched Izod impact strength of the neat PBT and neat PTT by 85.6 and 98.6 %, respectively. It shows an excellent toughening of PBT and PTT with ULDPE- g-GMA rubber. It was further found that the incorporation of only 3 wt% organoclay significantly improved the tensile strength, tensile modulus values of PBT/PTT blends. The result of FEG-SEM indicated that nanocomposite with 3 wt% organoclay in PBT/PTT/2wt% ULDPE-g-GMA did not show phase separation. It showed that 3 wt% organoclay was homogeneously dispersed in impact modified PBT/PTT blends based nanocomposites. POM studies revealed that the well-defined spherulites are present in neat PBT and neat PTT when $$T_{\mathrm{c}}$$ was 205 $${^{\circ }}$$ C.

Effect of Compatibilization on Biobased Rubber-Toughened Poly(trimethylene terephthalate): Miscibility, Morphology, and Mechanical Properties.

Fabrication of partially biobased poly(trimethylene terephthalate) (PTT) elastomeric blends was done via melt processing. Both natural rubber (NR) and epoxidized NR (ENR) were investigated as impact modifiers at 40 wt % loading to avoid lowering the overall biobased content of the blend system below that of the PTT alone (35% renewable content), along with maleated polybutadiene rubber (MR) and dicumyl peroxide (DCP) as reactive compatibilizers. The compatibility of the blend components was investigated using contact angle, rheometry, and scanning electron microscopy (SEM). The interfacial tensions and work of adhesions indicated that ENR was more miscible than NR in the PTT blend system, which was corroborated by the higher shear viscosity of the ENR blends and strong shear thinning behavior. Additionally, the predictive modeling of viscosity ratios on the elastomer–thermoplastic morphology was found to match the SEM micrographs with the dispersed elastomeric phase within the PTT matrix. The SEM images of the blends also establish that both the compatibilizers reduced the rubber inclusions size, though DCP hampered the impact performance as compared to the MR. In the presence of the MR, there was an increased cross-linking and observed variation in the Fourier transform infrared peaks demonstrating chemical interactions between the maleic anhydride groups with the PTT that allowed for the impact strength to reach 137 J·m–1 or 4.5 times that of the neat PTT, with the modulus of toughness increased by 82% and an elongation at yield of 50% because of the flexibility and amorphous nature of the rubber constituent.

Interfacial interactions in PTT\u2013PTMO/polyhedral oligomeric silsesquioxane (POSS) nanocomposites and their impact on mechanical, thermal, and dielectric properties

Poly(trimethylene terephthalate–block–tetramethylene oxide) (PTT–PTMO)/polyhedral oligomeric silsesquioxane (POSS) nanocomposites, synthesized by in situ polymerization, are characterized in detail in terms of interfacial interactions between functional groups on the surface of POSS and polymer chains. The impact of POSS incorporation on the molecular mobility is investigated by means of dielectric spectroscopy. It is found that PTT–PTMO/POSS nanocomposites exhibit higher values of stress at strain of 100% that in comparison with neat PTT–PTMO might result from the influence of POSS particles on the molecular mobility of polymer chains, which is probably due to the interfacial interactions between functional groups on the surface of POSS particles with the polymer matrix. Moreover, it is found that there is no variation of the segmental relaxation for the nanocomposite investigated and there is an increase in the interfacial polarization induced by the presence of POSS as seen in the increment of the real part of the dielectric permittivity.

Synthesis of a deoxybenzoin derivative and its use as a flame retardant in poly(trimethylene terephthalate)

ABSTRACTA Friedel–Crafts acylation reaction was used to synthesize a deoxybenzoin derivative named bis[2,6‐dimethyl‐4‐(2‐phenyl acetyl)phenyl]phenyl phosphonate (BDPP), which could be used as a flame‐retardant additive in poly(trimethylene terephthalate) (PTT) resin. The limited oxygen index and cone calorimetry tests indicated that the introduction of 5 wt % BDPP significantly improved the flame‐retardant properties of PTT through a synergistic char‐formation mechanism in the condensed phase and a flame‐inhibition mechanism in the gas phase. The PTT–BDPP blend also demonstrated an evident reduction in the melt viscosity but a superior melt stability in comparison to the neat PTT. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45904.

Transcrystallization of polypropylene in the presence of polyester/cellulose nanocrystal composite fibers

Pristine cellulose nanocrystal (CNC) and acetylated one (aCNC) were used as the modifier to change the surface properties of poly(trimethylene terephthalate) (PTT) fibers for the transcrystallization study of polypropylene (PP). The results reveal that all three kinds of fibers, including the neat PTT, PTT/CNC and PTT/aCNC ones can induce PP transcrystallization. But the PTT/aCNC fiber-filled PP system shows the most remarkable transcrystallization behavior because of the highest nucleation density of PTT/aCNC fiber. The long period and lamellar thickness of two composite fiber-filled PP systems increase as compared with the neat PTT fiber-filled one, which is caused by the reduced system undercooling and higher surface energy level of composite fibers. Accordingly, the former two systems show the lower transcrystal growth rates than the latter, which is further analyzed by the secondary nucleation theory. This work can provide useful information on the control of PP transcrystallization using the CNC-filled polyester composite fibers.

Comparative study on the properties of poly(trimethylene terephthalate) -based nanocomposites containing multi-walled carbon (MWCNT) and tungsten disulfide (INT-WS2) nanotubes

Multi-walled carbon (MWCNT) and tungsten disulfide (INT-WS2) nanotubes are materials with excellent mechanical properties, high electrical and thermal conductivity. These special properties make them excellent candidates for high strength and electrically conductive polymer nanocomposite applications. In this work, the possibility of the improvement of mechanical, thermal and electrical properties of poly(trimethylene terephthalate) (PTT) by the introduction of MWCNT and INT-WS2 nanotubes was investigated. The PTT nanocomposites with low loading of nanotubes were prepared by in situ polymerization method. Analysis of the nanocomposites' morphology carried out by SEM and TEM has confirmed that well-dispersed nanotubes in the PTT matrix were obtained at low loading (<0.5 wt%). Thermal and thermo-oxidative stability of nanocomposites was not affected by the presence of nanotubes in PTT matrix. Loading with INT-WS2 up to 0.5 wt% was insufficient to ensure electrical conductivity of PTT nanocomposite films. In the case of nanocomposites filled with MWCNT, it was found that nanotube incorporation leads to increase of electrical conductivity of PTT films by 10 orders of magnitude, approaching a value of 10−3 S/cm at loading of 0.3 wt%. Tensile properties of amorphous and semicrystalline (annealed samples) nanocomposites were affected by the presence of nanotubes. Moreover, the increase in the brittleness of semicrystalline nanocomposites with the increase in MWCNT loading was observed, while the nanocomposites filled with INT-WS2 were less brittle than neat PTT. Copyright © 2016 John Wiley & Sons, Ltd.

Morphological features and crystallization behavior of the conductive composites of poly(trimethylene terephthalate)/graphene nanosheets

ABSTRACTPoly(trimethylene terephthalate) (PTT) composites filled with well‐dispersed graphene nanosheets (GNSs) were prepared through a coagulation method. The effects of increased GNS concentration on variations in the structure and properties of the PTT matrix, such as its electrical conductivity, crystallization kinetics, melting behavior, and crystal morphology, were investigated. Several analytical techniques were used, including electrical conductivity measurement, differential scanning calorimetry, Fourier transform infrared spectroscopy, wide‐angle X‐ray diffraction, polarized light microscopy, transmission electron microscopy (TEM), and thermo‐gravimetric analysis (TGA). Electrical conductivity increased from 1.8 × 10−17 S/cm for neat PTT to 0.33 ± 0.23 S/cm for PTT/GNS composites with 2.97 vol % GNS content. Percolation scaling laws were applied, and then threshold concentration and exponent were determined. In the case wherein liquid nitrogen was used to quench the melt, a mesomorphic phase was formed despite the extremely short crystallization time after adding high GNS contents. PTT crystallization rate increased with the gradual addition of GNSs. The enhanced crystallization kinetics was attributed to the high nucleation ability of GNSs to induce epitaxially grown lamellae on their surfaces, as revealed by TEM. PTT nuclei were randomly developed on the GNS surface to form the lamellae. However, crystallinity reached its maximum value near the electrical percolation threshold because the PTT chain mobility was confined after the GNS–GNS network formed. The growth of PTT banded spherulites in the bulk was still observed for composites with high GNS content, and TGA results revealed that the GNS‐filled PTT composites had excellent thermal stability. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43419.

Effect of clay on melt crystallization, crystallization kinetics and spherulitic morphology of poly(trimethylene terephthalate) nanocomposites

Poly(trimethylene terephthalate) (PTT)/clay nanocomposite films have been prepared via a novel two-step approach. The resulting nanocomposites have been characterized by Fourier transform infrared spectroscopy (FTIR), wide angle X-ray diffraction (XRD), differential scanning calorimetry (DSC) and polarized light microscopy (PLM). XRD results showed this two-step process of preparation forms predominantly exfoliated structures. The effect of nanoclay on the isothermal and nonisothermal melt crystallization behaviors of PTT has been investigated and shown that the incorporation of clay accelerates the rate of crystallization and increases the total crystallinity of PTT nanocomposites compared to neat PTT. Nonisothermal melt crystallization kinetics of neat PTT and PTT nanocomposites was analyzed using crystallization isotherm. The Avrami analysis modified by Jeziorny was successfully used to describe the non-isothermal crystallization kinetics of neat PTT and PTT nanocomposites, shown by the decrease in half time (t1/2) of crystallization and increase in rate constant (Zc) as organoclay content increased up to 10%. FTIR spectroscopy has been utilized for the first time to monitor conformational changes during the melt crystallization of PTT nanocomposites. It was demonstrated that the amorphous trans conformation transforms into the crystalline gauche conformation with increasing clay content, which suggests that nanoclay accelerates the polymer chain conformational transition from trans to gauche conformation. No significant change in amorphous gauche conformation was observed either with crystallization temperature or clay content.

Effect of multi-walled carbon nanotubes on mechanical and rheological properties of poly(trimethylene terephthalate)

This paper investigates rheological and mechanical properties of poly(trimethylene terephthalate) (PTT) in presence of multi-walled carbon nanotubes (MWCNTs). Morphological characterization by scanning electron microscope and transmission electron microscope showed uniform distribution of MWCNTs in the PTT matrix. Incorporation of MWCNTs into PTT matrix resulted in higher complex viscosity (η), storage (G′) and loss modulus (G″) than those of neat PTT, especially in low-frequency region. The dramatic increase in melt viscosity of PTT observed upon incorporation of MWCNTs in the range of 0.25–1 wt% could be due to the formation of interconnected network of MWCNTs in the polymer matrix, and thus, this can be regarded as rheological percolation threshold concentration. Cole–Cole plot showed change in slope and also shift in G′ versus G″ plot, which suggested change in microstructure upon MWCNT addition. The reinforcing effect of MWCNTs was also confirmed by dynamic mechanical analysis, where, by adding CNTs, a noticeable increase in storage modulus of PTT was observed. However, addition of MWCNTs showed no significant effect on the tensile properties of PTT due to poor interfacial interaction between CNTs and polymer matrix.

Crystallization under One-Dimensional Confinement in Alumina Nanopores of Poly(trimethylene terephthalate) and Its Composites with Single Wall Carbon Nanotubes

We report the preparation of semicrystalline polymer nanorods of PTT and of its nanocomposites with SWCNTs by infiltration of the molten polymer into disordered anodic alumina membranes. An accurate study of the crystalline orientation of these systems has been accomplished by means of X-ray microdiffraction. While polymer residual film exhibits isotropic character, edge-on lamellae are formed upon approaching the polymer/membrane interface. This effect might be due to the elongational flow that takes place in the molten state as polymer chains infiltrate the AAO membrane. At the interface, edge-on and flat-on crystalline lamellae coexist as a consequence of the strong interaction between the polymer and the AAO surface. Inside the nanopores, the confined environment induces a kinetic selection of polymer crystals which only allows the growth of crystalline lamellae with its a-axis parallel to that of the pore. In the case of PTT/SWCNT nanocomposites, this effect, in conjunction with the strong interaction between polymer and AAO surface, seems to prevail over the templating effect of the carbon nanotubes and a similar orientation to that of the neat PTT case is observed.

Crystallization behavior of poly(trimethylene terephthalate)/mesoporous silica SBA-15 composites prepared by in situ polymerization

Poly(trimethylene terephthalate)/mesoporous silica SBA-15 composites were prepared by in situ hybridization for the crystallization study. The results show that SBA-15 particles are well compounded with PTT, forming nanostructured composite system. Although the addition of SBA-15 particles results in an evident decrease of PTT molecular weight, those well dispersed mesoporous particles can compensate effectively for the property degradation of PTT. Besides, the addition of SBA-15 particles has large influence on the crystallization of PTT. The composites show higher crystallization temperature and rate than that of the neat PTT. But the presence of SBA-15 impedes PTT chain segment movements somewhat. In comparison with neat PTT, therefore, the composites present lower folding surface free energy and higher diffusion activation energy. The kinetic analysis results elucidate that the crystallization rate of PTT is dominated by the nucleation item instead of the growth one.

Synthesis and characterization of poly(trimethylene terephthalate)/organoclay nanocomposite via in situ polymerization

Neat poly(trimethylene terephthalate) (PTT) and PTT/modified organoclay nanocomposite with various amounts of clay were synthesized by a two-step procedure. Terephthalic acid (TPA) was reacted with 1,3-propanediol (1,3-PDO) in the esterification step. Then, polycondensation reaction resulted in the formation of PTT in the presence of tetra buthyl titanate (Ti(OC4H9)4) as a catalyst. Commercially available organoclay (Cloisite 30B) was modified using 3-aminopropyltriethoxysilane via a silylation reaction. Thermal stability of modified clay was studied by means of thermal gravimetric analysis (TGA) that showed 10% less weight loss than Cloisite 30B. PTT/organoclay nanocomposites with 0.5, 1 and 2 wt% of modified organoclay were prepared by in situ polymerization. Synthesized polyesters were characterized by Fourier-transform infrared spectroscopy and proton-nuclear magnetic resonance spectroscopy (1H-NMR). Number average molecular weights were determined by 1H-NMR and a new Mark–Houwink equation is reported for highly pure dichloroacetic acid as solvent at 25°C. Polymer’s morphology was examined with x-ray diffraction and transmission electron microscopy. It was observed that clay layers were not accumulated. Thermal properties and crystallization behavior were investigated by differential scanning calorimetry and TGA. Crystallization temperature ( Tc) of nanocomposites increased about 6°C compared to neat PTT that reflects greater overall crystallization. Modified Averami Equation was used to describe crystallization kinetics and crystal size was studied using polarized optical microscopy. It was observed that crystal size reduces with nanoclay content. PTT mostly is used as polymeric fiber. Hence, dyeability of neat PTT and nanocomposites was investigated using a spectrophotometer. About 32% increase in color uptake was determined.

Rheologic and mechanical properties of multiwalled carbon nanotubes-reinforced poly(trimethylene terephthalate) composites

This paper investigates the rheologic and mechanical properties of melt-blended poly(trimethylene terephthalate) (PTT)/multiwalled carbon nanotube (MWCNT) composites and the effect of acid treatment of MWCNT on these properties. The microstructure of the composites was studied by SEM and TEM in terms of the dispersion state of the nanotubes and the polymer–nanotube interaction. Incorporation of MWCNTs into PTT matrix resulted in an increase in both complex viscosity and moduli than those of neat PTT. A dramatic increase in the melt viscosity of composites observed with loading of MWCNT in the range of 0.5 and 2 wt% showed the formation of interconnected network of MWCNT in the polymer matrix at a rheologic percolation threshold. Acid treatment of MWCNT showed significant effect on the rheologic properties of PTT and led to the enhancement of both complex viscosity and moduli due to strong interfacial interaction between acid-treated MWCNT and PTT matrix. The effect of acid treatment was also evident by mechanical properties of the PTT/MWCNT composites. The untreated MWCNT showed only increase in modulus of PTT matrix; whereas, after acid treatment, both tensile strength and modulus of PTT matrix enhanced significantly.

Block phosphorus-containing poly(trimethylene terephthalate) copolyester via solid-state polymerization: retarded crystallization and melting behaviour

The crystallization behavior of neat PTT and phosphorus-containing PTT copolyester with specific block chain structure (PTTDs, obtained by solid-state polymerization (SSP)) has been investigated by differential scanning calorimetry (DSC), polarized microscopy (POM) and wide-angle X-ray diffraction (WAXD). The overall crystallization kinetics study shows that crystallization is retarded with introduction of a phosphorus-containing segment. This retardation effect is obvious for PTTD10; however, no greater retardation can be observed with further increasing the phosphorus content, which is attributed to the hindering effect of phosphorus-containing segment and specific chain structure, and is in accordance with the crystallization morphology. The crystallization rate of PTTDs is much lower at high crystallization temperature than that of PTT, which can be explained by the diluent effect of the non-crystallizable chain segment. The result of spherulite growth is in accordance with DSC study. The rigid amorphous fraction (RAF) is also calculated, which increases with increasing phosphorus content, suggesting that RAF is not the main factor for retarded crystallization. The main factors of retarded crystallization are probably caused by the diluent effect and the hindering effect of the specific chain structure. With incorporation of phosphorus-containing segments, the transition temperature is slightly changed; however, the equilibrium melting temperature (Tm0) of the copolyester decreases. The phosphorus-containing segment plays the role of nucleation agent at regime III.

Phosphorus-containing poly(trimethylene terephthalate) derived from 2-(6-oxido-6H-dibenz〈c,e〉〈1,2〉oxaphosphorin-6-yl)-1,4-hydroxyethoxy phenylene: Synthesis, thermal degradation, combustion and pyrolysis behavior

A novel phosphorus-containing poly(trimethylene terephthalate) (PTT) derived from 2-(6-oxido-6H-dibenz〈c,e〉〈1,2〉oxaphosphorin-6-yl)-1,4-hydroxyethoxy phenylene was synthesized via solid state polymerization, and its chemical structure was confirmed with 1H NMR. The thermal stability of the resulting copolyester was analyzed by thermogravimetric analysis. With the introduction of phosphorus-containing segments, polyester onset weight-loss temperatures in both nitrogen and air are enhanced. Thermal degradation kinetics were analyzed using the Flynn–Wall–Ozawa method, which showed a decreased activation energy for the copolyester compared with that for neat PTT, strongly suggesting that the increased onset weight-loss temperature in nitrogen is a result of enhanced carbonization. Microscale combustion calorimetry was carried out to test the flammability behavior of the copolyester; improved flame-retardant properties were observed with incorporated phosphorus components. Py-GC–MS testing revealed that the pyrolysis of phosphorus-containing copolyester is not significantly affected by the phosphorus incorporation.

Thermal, mechanical, and morphological investigation of injection molded poly(trimethylene terephthalate)/carbon fiber composites

AbstractInjection molded poly(trimethylene terephthalate) (PTT)/carbon fiber (CF) composites have been fabricated using a twin screw micro compounder. The effect of CF reinforcement on the thermal, mechanical, dynamic mechanical, and microscopic properties of the composite was investigated. Addition of 30 wt% of CF into PTT resulted in the significant enhancement of tensile (120%) and flexural (30%) strength compared to neat PTT. The rule of mixture was successfully employed for theoretical calculations of tensile modulus and the calculated values were compared with the experimental results. Similarly, CF reinforced (30 wt%) PTT composites exhibited an increase of more than a 150°C in the heat deflection temperature. Scanning electron microscopy analysis of the tensile fracture specimens revealed uniform distribution of the CFs with good polymer matrix and fiber adhesion. Overall, the results obtained indicate the enhancement of properties with increasing fiber content, confirming better fiber and polymer matrix compatibility. POLYM. COMPOS., 33:1933–1940, 2012. © 2012 Society of Plastics Engineers