The use of Rheology Combined with Differential Scanning Calorimetry to Elucidate the Granulation Mechanism of an Immiscible Formulation During Continuous Twin-Screw Melt Granulation

2016 ◽  
Vol 33 (10) ◽  
pp. 2481-2494 ◽  
Author(s):  
Tinne Monteyne ◽  
Liza Heeze ◽  
Severine Therese F. C. Mortier ◽  
Klaus Oldörp ◽  
Ruth Cardinaels ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Scanning Calorimetry ◽  
Twin Screw ◽  
Granulation Mechanism ◽  
Melt Granulation

Step-Scan DSC Study on the Melting Behavior of Polypropylene/Attapulgite Nanocomposites

2011 ◽  
Vol 284-286 ◽  
pp. 763-768
Author(s):  
Li Li Sun ◽  
Kun Hu ◽  
Lin Chen ◽  
Kang Zheng ◽  
Xing You Tian
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Differential Scanning Calorimetry ◽  
Melting Behavior ◽  
Secondary Crystallization ◽  
Screw Extruder ◽  
Scanning Calorimetry ◽  
Twin Screw ◽  
Multiple Melting ◽  
Scanning Electron

Attapulgite(AT) was modified by grafting with butyl acrylate(BA) via polymerizations initiated by Gamma radiation. The polypropylene(PP)/AT nanocomposites were synthesized via melting extrude in a twin-screw extruder. The thermogravimetry(TG) and scanning electron microscopy (SEM) were used to assess the graft ratio of the hybrid materials and the dispersion of AT, respectively. Step-scan differential scanning calorimetry(SSDSC) was used to study the influence of AT on the crystallization and subsequent melting behavior. The results indicated that PP and PP/AT nanocomposites underwent multiple melting and secondary crystallization processes during heating. The melting behaviours of PP and PP/AT nanocomposites varied with the variation of crystallization temperature and AT content.

Crystal Morphology and Thermal Properties of PA6/PP-g-MAH/POE Blends

2011 ◽  
Vol 366 ◽  
pp. 314-317
Author(s):  
Ming Tao Run ◽  
Wen Zhou ◽  
Bing Tao Xing ◽  
Meng Yao
Keyword(s):  
Differential Scanning Calorimetry ◽  
Thermal Properties ◽  
Crystal Morphology ◽  
Crystallization Rate ◽  
Screw Extruder ◽  
Scanning Calorimetry ◽  
Acicular Crystal ◽  
Polarized Optical Microscopy ◽  
Twin Screw ◽  
Higher Temperature

The crystal morphology and thermal properties of the PA6/PP-g-MAH/POE blends prepared by twin-screw extruder were studied by polarized optical microscopy (POM) and differential scanning calorimetry (DSC) respectively. The results suggest that the crystal morphology of PA6 is acicular crystal while PP-g-MAH is micro-spherulites; The acicular crystals form across POE phase to PA6 phase, and the acicular crystals of PA6 in the POE phase have better regularity in dimension than those in amorphous PA6 phase. Acting as a compatibilizer, PP-g-MAH improves the miscibility of PA6 and POE, leading to the glass transition temperature of the blends decreases gradually with increasing POE contents. PA6 and PP-g-MAH can crystallize individually, and the formed PA6 crystals induced the crystallization of PP-g-MAH at higher temperature; furthermore, PP-g-MAH and POE components can increase the crystallization rate of PA6.

scholarly journals Effects of Humidity on the Dissolution Profiles of Controlled Release Theophylline Matrix Tablets Containing Release Enhancers Prepared By Melt Granulation and Coacervation Techniques

2020 ◽  
Vol 24 (9) ◽  
pp. 1563-1567
Author(s):  
J.A. Avbunudiogba
Keyword(s):  
Differential Scanning Calorimetry ◽  
Controlled Release ◽  
Relative Humidity ◽  
Drug Release ◽  
Chemical Properties ◽  
Modern Technology ◽  
Matrix Tablets ◽  
Scanning Calorimetry ◽  
Physical Chemical ◽  
Melt Granulation

The quantity of moisture present in tablets plays a major role in influencing the physical/chemical properties of tablets especially dissolution profiles. The purpose of the present study is to investigate the effects of relative humidity on the dissolution profiles of controlled release  theophylline matrix tablets containing release enhancer prepared by melt granulation and simple coacervation techniques. Sucrose and  microcrystalline cellulose at concentration of 3% w/w, 5% w/w, 7.5% w/w, and 10% w/w were included in the blends as release enhancers before compression into nondisintegrating matrix tablets. Resulting tablets were exposed to 0% and 75% relative humidity. Sample were withdrawn at 0, 15 days, 1 month, 2 months and 3 months and evaluated for cumulative drug release. Interactions were investigated using modern technology: Differential scanning calorimetry (DSC). Initial and maximum release were increased after exposure to 75% relative humidity. There was no drug – excipients interaction. Thus moisture increased theophylline release from both sets of tablets prepared by melt granulation and simple coacervation techniques. Keywords: Theophylline, Matrix tablets, Dissolution profiles, Release enhancers, Relative humidity

A Comparative Study on the Effect of Adiabatic Extrusion by Twin-Screw Extruder to the Crystallization Pattern and Thermal Behavior of Polyamide 6/C20A Nanocomposites

2013 ◽  
Vol 756 ◽  
pp. 135-142 ◽  
Author(s):  
Zulhelmi Ismail ◽  
Kamal Yusoh
Keyword(s):  
Differential Scanning Calorimetry ◽  
Thermal Degradation ◽  
Polyamide 6 ◽  
Combination Effect ◽  
Gravimetric Analysis ◽  
Twin Screw Extruder ◽  
Screw Extruder ◽  
Scanning Calorimetry ◽  
Mass Losses ◽  
Twin Screw

The performance of an adiabatic extrusion in minimizing the risk of thermal degradation for PA6/C20A nanocomposites was investigated in this paper. The screw speed of twin-screw extruder was maintained at constant value of 100 RPM while the clay loadings C20A were varied between 1 wt %, 3wt % and 5 wt % respectively.Thermal gravimetric analysis was used to characterize the thermal property of polyamide6/C20A-nanocomposites and the crystallization pattern was thoroughly examined via the application of differential scanning calorimetry. The time taken for 10 wt.% mass losses of majority adiabatic extruded samples was observed to be longer as compared to the conventional extruded PA6/C20A samples. The combination effect of adiabatic extrusion and nanoclay presence in the PA6-matrix has managed to increase thermal resistant of PA6. The crystallinity grade for each of the samples with different loading of C20A. however has not diversed in value since the index of crystallinity (Xc) remains independent of C20-volume althoughconventional/adiabatic setting of extruder could possibly have greater effect on the crystalline feature of PA6/C20A nanocomposites.

Thermal Stability of N-Heterocycle-Stabilized Iodanes – A Systematic Investigation

2019 ◽  
Author(s):  
Andreas Boelke ◽  
Yulia A. Vlasenko ◽  
Mekhman S. Yusubov ◽  
Boris Nachtsheim ◽  
Pavel Postnikov
Keyword(s):  
Thermal Stability ◽  
Differential Scanning Calorimetry ◽  
Thermogravimetric Analysis ◽  
Systematic Investigation ◽  
Scanning Calorimetry ◽  
Thermal Stability Of

<p>The thermal stability of pseudocyclic and cyclic <i>N</i>-heterocycle-stabilized (hydroxy)aryl- and mesityl(aryl)-l<sup>3</sup>-iodanes (NHIs) through thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) is investigated. NHIs bearing <i>N</i>-heterocycles with a high N/C-ratio such as triazoles show among the lowest descomposition temperatures and the highest decomposition energies. A comparison of NHIs with known (pseudo)cyclic benziodoxolones is made and we further correlated their thermal stability with reactivity in a model oxygenation. </p>

Optimasi Proses Pembuatan dan Karakterisasi Fisik Niosom Sinkonin

2019 ◽  
Vol 16 (2) ◽  
pp. 178
Author(s):  
Hariyanti Hariyanti ◽  
Sophi Damayanti ◽  
Sasanti Tarini
Keyword(s):  
Differential Scanning Calorimetry ◽  
Particle Size ◽  
Hair Follicle ◽  
Scanning Calorimetry ◽  
Span 60

Sinkonin praktis tidak larut dalam air, sedikit larut dalam kloroform dan alkohol. Hal ini berdampak pada rendahnya penetrasi transfollicular sinkonin, karena hanya bahan aktif hidrofilik yang mampu melewati hair follicle. Dengan demikian dibutuhkan satu sistem penghantaran yang mampu menurunkan hidrofobisitas sinkonin untuk meningkatkan penetrasi sinkonin ke follicle. Niosom merupakan vesikel ampifilik dengan struktur lapisan rangkap yang terbentuk dari hidrasi kombinasi surfaktan nonionik dan kolesterol yang mampu menurunkan hidrofobisitas sinkonin. Penelitian ini bertujuan untuk menentukan proses pembuatan niosom sinkonin yang optimum. Pembuatan niosom sinkonin diawali dengan menentukan temperatur gelasi (Tg) dari span 60 dengan Differential Scanning Calorimetry (DSC), kemudian dilanjutkan dengan optimasi proses meliputi: optimasi kecepatan rotavapor pembentukan film lapis tipis, temperatur hidrasi, kecepatan rotavapor hidrasi, waktu hidrasi, dan waktu sonikasi. Karakteristik vesikel niosom yang optimal meliputi: ukuran partikel dan indeks polidispersitas dengan menggunakan Particle Size Analized (PSA) serta efisiensi penjeratan sinkonin dengan menggunakan KCKT. Temperatur gelasi (Tg) span 60 45±2 oC, kecepatan rotavapor pembentukan film lapis tipis niosom 210 rpm, temperatur hidrasi 55±2 oC, kecepatan rotavapor hidrasi 210 rpm, waktu hidrasi 20 menit, waktu sonikasi suspensi niosom 1 menit. Ukuran vesikel yang diperoleh adalah 100–200 nm, indeks polidispersitas 0,2–0,4 dan efisiensi penjeratan niosom sinkonin 84,49±0,0025%. Proses pembuatan niosom sinkonin memiliki pengaruh besar terhadap hasil ukuran vesikel dan efisiensi penjeratan niosom sinkonin.

Improving Wire Sweep Performance by Measuring Degree of Cure of Epoxy Mold Compounds

2011 ◽  
Author(s):  
Sheila Liza B. Dal
Keyword(s):  
Differential Scanning Calorimetry ◽  
Shelf Life ◽  
Trial And Error ◽  
Active Components ◽  
Scanning Calorimetry ◽  
Degree Of Cure ◽  
Electronic Package ◽  
Viscosity Changes ◽  
Epoxy Mold Compounds

Abstract The choice of epoxy mold compound (EMC) for an electronic package is based mostly on how much protection it provides to the active components in the package. But the choice is not a straightforward process. Rather it is mostly trial and error using different assembly parameters to find the most robust material while assembly defects are monitored. One such defect associated to EMC processing is wire sweep, and many studies have shown that it is mainly caused by viscosity changes in the EMC. In this study, samples of EMC in various stages of shelf life and staging times were analyzed for degree of cure using a method called differential scanning calorimetry (DSC). Samples are then processed at assembly for wire sweep measurement. It was found out that degree of cure increases with staging time at different rates for each shelf life. It was also found out that wire sweep did not only increase with degree of cure but it was also found to be predictable with respect to the latter. Using this information, the age and staging limit for each material was identified that would not cause wire sweep issues.

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