Properties of glass-filled thermoplastic polyesters

Chisholm, Bret J.; Fong, Peter; Zimmer, Jochen; Hendrix, R.

doi:10.1002/(sici)1097-4628(19991024)74:4<889::aid-app15>3.0.co;2-r

Cited by 26 publications

(9 citation statements)

References 21 publications

(22 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Another approach to increase the glass transition temperature is to increase the molecular weight of PBT using technologies of chain extension/branching or copolymerization [4][5][6]. Manufacturing the filled composites such as glass fiber reinforced PBT is also proved to be an effective way to obtain superior properties [7].…”

Section: Introductionmentioning

confidence: 99%

Crystallization and thermal behavior of multiwalled carbon nanotube/poly(butylenes terephthalate) composites

et al. 2008

Polymer Engineering & Sci

View full text Add to dashboard Cite

Multiwalled carbon nanotube/poly(butylene terephthalate) composites (PCTs) were prepared by melt mixing. The nonisothermal crystallization and thermal behavior of PCTs were respectively investigated by X-ray diffractometer, polarized optical microscope, differential scanning calorimeter, dynamic mechanical thermal analyzer, and thermogravimetric analyzer. The presence of nanotubes has two disparate effects on the crystallization of PBT: the nucleation effect promotes kinetics, while the impeding effect reduces the chain mobility and retards crystallization. The kinetics was then analyzed using Ozawa, Mo, Kissinger, Lauritzen-Hoffman, and Ziabicki model, and the results reveal that the nucleation effect is always the dominant role on the crystallization of PBT matrix. Thus the crystallizability increases with increase of nanotube loadings. In addition, the presence of nanotubes nearly has no remarkable contribution to thermal stability because nanotubes also play two disparate roles on the degradation of PBT matrix: the Lewis acid sites to facilitate decomposition and the physical hindrance to retard decomposition. Hence the nanotubes act merely as inert-like filler to thermal stability. FIG. 5. Avrami plots of log[Àln(1 À X(T))] vs. log t for the PCT1 sample at various cooling rates. FIG. 6. Ozawa plots of log[Àln(1 À X(T))] vs. ln / for (a) the PCT1 and (b) PCT5 samples.

show abstract

Section: Introductionmentioning

confidence: 99%

Crystallization and thermal behavior of multiwalled carbon nanotube/poly(butylenes terephthalate) composites

et al. 2008

Polymer Engineering & Sci

View full text Add to dashboard Cite

show abstract

“…18 Although the detailed mechanism of heterogeneous nucleation in polymers is not well understood, it is believed to arise from molecular interactions between the polymer and the surface of the nucleating agent. 19,20 This interaction results in a reduction in the interfacial free-energy barrier for stable nucleus formation. An increase in the overall crystallization rate occurs with a reduction of the nucleation induction period and an increase in the number of primary nucleation sites.…”

Section: Introductionmentioning

confidence: 99%

Polylactide stereocomplex crystallites as nucleating agents for isotactic polylactide

Schmidt¹

2001

J. Polym. Sci. B Polym. Phys.

117

View full text Add to dashboard Cite

A nucleation efficiency scale for isotactic poly(L-lactide) (PLLA) was obtained with self-nucleation and nonisothermal differential scanning calorimetry experiments. The maximum nucleation efficiency occurred at the highest concentration of self-nucleating sites, and the minimum efficiency occurred in the absence of these sites (pure PLLA polymer melt). Blends of PLLA and isotactic poly(D-lactide) (PDLA) led to the formation of a 1/1 stereocomplex. In comparison with the homopolymer (PLLA), the stereocomplex had a higher melting temperature and crystallized at higher temperatures from the melt. Small stereocomplex crystallites were formed in PLLA/PDLA blends containing low concentrations of PDLA. These crystallites acted as heterogeneous nucleation sites for subsequent PLLA crystallization. Using the PLLA nucleation efficiency scale, we evaluated a series of PLLA/PDLA blends (0.25-15 wt % PDLA). A maximum nucleation efficiency of 66% was observed at 15 wt % PDLA. The nucleation efficiency was largely dependent on the thermal treatment of the sample. The nucleating ability of the stereocomplex was most efficient when it was formed well before PLLA crystallization. According to the efficiency scale, the stereocomplex was far superior to talc, a common nucleating agent for PLLA, in its ability to enhance the rate of PLLA crystallization. In comparison with the PLLA homopolymer, the addition of PDLA led to reduced spherulite sizes and a reduction in the overall extent of PLLA crystallization. The decreased extent of crystallization was attributed to the hindered mobility of the PLLA chains due to tethering by the stereocomplex.

show abstract

“…The data obtained suggested that, even with the addition of nucleating agents, injection‐molded materials based on PPT would not possess the same level of performance in terms of cycle time as PBT materials compounded in the absence of a nucleating agent. Previous work, which involved an investigation of the effect of talc and sodium stearate on the mechanical and viscoelastic properties of glass‐filled PPT and analogous PBT materials, provides support for this conclusion 7…”

Section: Resultsmentioning

confidence: 69%

“…This decision was the result of a new process innovation for the production of 1,3‐propanediol at a much lower cost 2. The fiber properties of PPT have been the subject of several reports,3–6 whereas only a few reports describe the properties of injection‐molded specimens 1, 7…”

Section: Introductionmentioning

confidence: 99%

Isothermal crystallization kinetics of commercially important polyalkylene terephthalates

Chisholm

Zimmer

2000

J. Appl. Polym. Sci.

Self Cite

View full text Add to dashboard Cite

The isothermal crystallization kinetics of virgin, melt‐mixed, and nucleated specimens of polyethylene terephthalate (PET), polypropylene terephthalate (PPT), and polybutylene terephthalate (PBT) were measured. The purpose of the study was to determine the difference in crystallization rate of PPT, which is to be commercially available in the near future, to the extensively studied, commercially important polyalkylene terephthalates PET and PBT. At equivalent supercooling, the crystallization rate of PPT was between that of PET and PBT, with PBT being the fastest crystallizing polymer. Melt‐mixing virgin materials resulted in a substantial increase in the crystallization rate for all three polyalkylene terephthalates. The addition of talc or sodium stearate as a nucleating agent resulted in a further increase in crystallization rate for all three polyesters. Although the addition of talc or sodium stearate to PPT and PET greatly enhanced crystallization rate, these nucleating agent–containing materials still did not crystallize as fast as PBT melt‐mixed in the absence of any intentionally added nucleating agents. Analysis of the crystallization kinetic data using the Avrami equation showed that melt‐mixing and the addition of sodium stearate resulted in an increase in the average Avrami exponent. This result suggested a change in the mechanism of nucleation toward more sporadic nucleation. For the sodium stearate–nucleated materials, the Avrami exponent was found to increase with increasing crystallization temperature, but a precise explanation of this behavior could not be provided without a knowledge of crystallite morphology. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 1296–1307, 2000

show abstract

Properties of glass-filled thermoplastic polyesters

Cited by 26 publications

References 21 publications

Crystallization and thermal behavior of multiwalled carbon nanotube/poly(butylenes terephthalate) composites

Crystallization and thermal behavior of multiwalled carbon nanotube/poly(butylenes terephthalate) composites

Polylactide stereocomplex crystallites as nucleating agents for isotactic polylactide

Isothermal crystallization kinetics of commercially important polyalkylene terephthalates

Contact Info

Product

Resources

About