Synthesis and characteristics of biobased copolyester for thermal shrinkage film

RSC Advances ◽  
2016 ◽  
Vol 6 (62) ◽  
pp. 57626-57633 ◽  
Author(s):  
Young Min Heo ◽  
Jun Mo Koo ◽  
Dong Ki Hwang ◽  
Jong Gun JaeGal ◽  
Sung Yeon Hwang ◽  
...  
Keyword(s):  
Thermal Shrinkage ◽  
Melt Polymerization ◽  
Trimethylene Glycol

A series of poly(1,4-cyclohexanedimethyl-trimethylene glycol terephthalate), (PCTG), co-polyesters were synthesized using 1,3-propanediol (PDO) and 1,4-cyclohexanedimethanol (CHDM) via melt polymerization.

scholarly journals Thermal Shrinkage Temperature of Intramuscular Collagen of Bulls and Steers

1984 ◽  
Vol 59 (3) ◽  
pp. 706-709 ◽  
Author(s):  
M. D. Judge ◽  
E. D. Aberle ◽  
H. R. Cross ◽  
B. D. Schanbacher
Keyword(s):  
Thermal Shrinkage ◽  
Shrinkage Temperature

scholarly journals Pressure Equilibrium Time of a Cyclic-Olefin Copolymer

Polymers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 2309
Author(s):  
Benedikt Roth ◽  
Dietmar Drummer
Keyword(s):  
Dynamic Compression ◽  
Flow Behavior ◽  
Superposition Principle ◽  
Applied Pressure ◽  
Thermal Shrinkage ◽  
Compression Rate ◽  
Rate Dependency ◽  
Equilibrium Time ◽  
Simulation Techniques ◽  
Pressure Equilibrium

Integrative simulation techniques for predicting component properties, based on the conditions during processing, are becoming increasingly important. The calculation of orientations in injection molding, which, in addition to mechanical and optical properties, also affect the thermal shrinkage behavior, are modeled on the basis of measurements that cannot take into account the pressure driven flow processes, which cause the orientations during the holding pressure phase. Previous investigations with a high-pressure capillary rheometer (HPC) and closed counter pressure chamber (CPC) showed the significant effect of a dynamically applied pressure on the flow behavior, depending on the temperature and the underlying compression rate. At a constant compression rate, an effective pressure difference between the measuring chamber and the CPC was observed, which resulted in a stop of flow through the capillary referred to as dynamic compression induced solidification. In order to extend the material understanding to the moment after dynamic solidification, an equilibrium time, which is needed until the pressure signals equalize, was evaluated and investigated in terms of a pressure, temperature and a possible compression rate dependency in this study. The findings show an exponential increase of the determined equilibrium time as a function of the holding pressure level and a decrease of the equilibrium time with increasing temperature. In case of supercritical compression in the area of a dynamic solidification, a compression rate dependency of the determined equilibrium times is also found. The measurement results show a temperature-invariant behavior, which allows the derivation of a master curve, according to the superposition principle, to calculate the pressure equilibrium time as a function of the holding pressure and the temperature.

scholarly journals Melt Polymerization of Acrylamide Initiated by Nucleophiles: A Route toward Highly Branched and Amorphous Polyamide 3

2021 ◽  
Vol 3 (4) ◽  
pp. 2018-2026
Author(s):  
David Edinger ◽  
Hansjoerg Weber ◽  
Ema Žagar ◽  
David Pahovnik ◽  
Christian Slugovc
Keyword(s):  
Melt Polymerization

scholarly journals Fire Resistance Behaviour of Geopolymer Concrete:An Overview

Buildings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 82
Author(s):  
Salmabanu Luhar ◽  
Demetris Nicolaides ◽  
Ismail Luhar
Keyword(s):  
Compressive Strength ◽  
Thermal Resistance ◽  
Building Materials ◽  
Elevated Temperatures ◽  
Construction Materials ◽  
Flexural Behavior ◽  
Thermal Shrinkage ◽  
Physico Chemical ◽  
The Impact ◽  
Loss Of Strength

Even though, an innovative inorganic family of geopolymer concretes are eye-catching potential building materials, it is quite essential to comprehend the fire and thermal resistance of these structural materials at a very high temperature and also when experiencing fire with a view to make certain not only the safety and security of lives and properties but also to establish them as more sustainable edifice materials for future. The experimental and field observations of degree of cracking, spalling and loss of strength within the geopolymer concretes subsequent to exposure at elevated temperature and incidences of occurrences of disastrous fires extend an indication of their resistance against such severely catastrophic conditions. The impact of heat and fire on mechanical attributes viz., mechanical-compressive strength, flexural behavior, elastic modulus; durability—thermal shrinkage; chemical stability; the impact of thermal creep on compressive strength; and microstructure properties—XRD, FTIR, NMR, SEM as well as physico-chemical modifications of geopolymer composites subsequent to their exposures at elevated temperatures is reviewed in depth. The present scientific state-of-the-art review manuscript aimed to assess the fire and thermal resistance of geopolymer concrete along with its thermo-chemistry at a towering temperature in order to introduce this novel, most modern, user and eco-benign construction materials as potentially promising, sustainable, durable, thermal and fire-resistant building materials promoting their optimal and apposite applications for construction and infrastructure industries.

scholarly journals Green TPUs from Prepolymer Mixtures Designed by Controlling the Chemical Structure of Flexible Segments

2021 ◽  
Vol 22 (14) ◽  
pp. 7438
Author(s):  
Paulina Kasprzyk ◽  
Ewa Głowińska ◽  
Paulina Parcheta-Szwindowska ◽  
Kamila Rohde ◽  
Janusz Datta
Keyword(s):  
Chemical Structure ◽  
Melt Flow Index ◽  
Molar Ratio ◽  
Flow Index ◽  
Step Method ◽  
Elongation At Break ◽  
Molecular Weights ◽  
Trimethylene Glycol ◽  
Hard Segments ◽  
A Chain

This study concerns green thermoplastic polyurethanes (TPU) obtained by controlling the chemical structure of flexible segments. Two types of bio-based polyether polyols—poly(trimethylene glycol)s—with average molecular weights ca. 1000 and 2700 Da were used (PO3G1000 and PO3G2700, respectively). TPUs were prepared via a two-step method. Hard segments consisted of 4,4′-diphenylmethane diisocyanates and the bio-based 1,4-butanodiol (used as a chain extender and used to control the [NCO]/[OH] molar ratio). The impacts of the structure of flexible segments, the amount of each type of prepolymer, and the [NCO]/[OH] molar ratio on the chemical structure and selected properties of the TPUs were verified. By regulating the number of flexible segments of a given type, different selected properties of TPU materials were obtained. Thermal analysis confirmed the high thermal stability of the prepared materials and revealed that TPUs based on a higher amount of prepolymer synthesized from PO3G2700 have a tendency for cold crystallization. An increase in the amount of PO3G1000 at the flexible segments caused an increase in the tensile strength and decrease in the elongation at break. Melt flow index results demonstrated that the increase in the amount of prepolymer based on PO3G1000 resulted in TPUs favorable in terms of machining.

scholarly journals Bias Truck Tire Deformation Analysis with Finite Element Modeling

2020 ◽  
Vol 10 (12) ◽  
pp. 4326
Author(s):  
Józef Pelc
Keyword(s):  
Incompressible Material ◽  
Axisymmetric Deformation ◽  
Thermal Shrinkage ◽  
Deformation Analysis ◽  
Truck Tire ◽  
Non Linear ◽  
Strain Relationship ◽  
Tire Modeling ◽  
Total Lagrangian Formulation

This paper presents a method for modeling of pneumatic bias tire axisymmetric deformation. A previously developed model of all-steel radial tire was expanded to include the non-linear stress–strain relationship for textile cord and its thermal shrinkage. Variable cord density and cord angle in the cord-rubber bias tire composite are the major challenges in pneumatic tire modeling. The variabilities result from the tire formation process, and they were taken into account in the model. Mechanical properties of the composite were described using a technique of orthotropic reinforcement overlaying onto isotropic rubber elements, treated as a hyperelastic incompressible material. Due to large displacements, the non-linear problem was solved using total Lagrangian formulation. The model uses MSC.Marc code with implemented user subroutines, allowing for the description of the tire specific properties. The efficiency of the model was verified in the simulation of mounting and inflation of an actual bias truck tire. The shrinkage negligence effect on cord forces and on displacements was examined. A method of investigating the influence of variation of cord angle in green body plies on tire apparent lateral stiffness was proposed. The created model is stabile, ensuring convergent solutions even with large deformations. Inflated tire sizes predicted by the model are consistent with the actual tire sizes. The distinguishing feature of the developed model from other ones is the exact determination of the cord angles in a vulcanized tire and the possibility of simulation with the tire mounting on the rim and with cord thermal shrinkage taken into account. The model may be an effective tool in bias tire design.

Kinetics of melt polymerization of maleic acid phthalic acids with propylene glycol

1994 ◽  
Vol 49 (24) ◽  
pp. 5053-5070 ◽  
Author(s):  
T. Salmi ◽  
E. Paatero ◽  
P. Nyholm ◽  
M. Still ◽  
K. Na¨rhi
Keyword(s):  
Propylene Glycol ◽  
Maleic Acid ◽  
Melt Polymerization ◽  
Phthalic Acids ◽  
Kinetics Of

scholarly journals p-HYDROQUINONE AND p-BENZOQUINONE AS HISTOCHEMICAL REAGENTS I. A NEW TETRAZOLIUM METHOD FOR AMINO GROUPS, AND THE MECHANISM OF FORMAZAN STAINING OF PARAFFIN AND FRESH FROZEN SECTIONS

1967 ◽  
Vol 15 (7) ◽  
pp. 404-408 ◽  
Author(s):  
G. G. CARMICHAEL ◽  
STEPHANIE T. K. MANDER
Keyword(s):  
Electron Acceptor ◽  
Thermal Shrinkage ◽  
Frozen Sections ◽  
Amino Groups ◽  
Paraffin Sections ◽  
Tetrazolium Bromide ◽  
Acid Ph ◽  
Reduction System ◽  
Oxidation Reduction ◽  
Fresh Frozen

The staining of amino groups by formazan when dehydrated paraffin sections are incubated in a mixture of hydroquinone and 3-(4,5-dimethyl thiazolyl-2)-2 ,5-diphenyl-2H-tetrazolium bromide at an acid pH is reported. The mechanism of this reaction and of the cytoplasmic deposition of formazan in fresh frozen sections incubated under similar conditions is investigated. It is shown that the oxidation of hydroquinone to semiquinone is responsible for the reaction, the tetrazole acting as electron acceptor. The tissue amino groups, exposed by dehydration and thermal shrinkage, and the nitrogen groupings of phosphobipid behave as "catalysts." The relevant properties of the hydroquinone-benzoquinone oxidation-reduction system are described, and the reactions between benzoquinone and tissue constituents are reviewed.

Durability of Cement Stabilized Cold-Recycled of Asphalt Pavement Materials

2012 ◽  
Vol 174-177 ◽  
pp. 1188-1192 ◽  
Author(s):  
Lian Yu Wei ◽  
Zhi Yu Guo
Keyword(s):  
Asphalt Pavement ◽  
Base Material ◽  
Road Construction ◽  
Thermal Shrinkage ◽  
Construction Process ◽  
Pavement Materials ◽  
Road Base ◽  
Wide Range ◽  
Dry Shrinkage ◽  
Recycled Material

In recent years, due to the dual pressures of resources and the environment,the clod recycled technology renovation and expansion of the old road and new road construction process increasingly attention increasingly wide range of applications. In this paper, the water stability of the cold recycled materials in asphalt pavement on cement additives, frozen stability, thermal shrinkage resistance, dry Shrinkage thefour indicators of experiments to evaluate its durability, and compared with the typical semi-rigid material. To verify the feasibility of the cold recycled material as road base material.

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