Structure-property relationships processes

The structure/property relationships in materials subjected to shock-wave deformation is physically very difficult to conduct and complex to interpret due to the dynamic nature of the shock process and the very short time of the test. Due to these imposed constraints, most real-time shock-process measurements are limited to studying the interactions of the transmitted waves arrival at the free surface. To augment these in situ wave-profile measurements, shock-recovery techniques were developed in the late 1950s to assess experimentally the residual effects of shock-wave compression on materials. The object of soft-recovery experiments is to examine the terminal structure/property relationships of a material that has been subjected to a known uniaxial shock history, then returned to an ambient pressure... 

To illustrate the effect of radial release interactions on the structure/ property relationships in shock-loaded materials, experiments were conducted on copper shock loaded using several shock-recovery designs that yielded differences in es but all having been subjected to a 10 GPa, 1 fis pulse duration, shock process [13]. Compression specimens were sectioned from these soft recovery samples to measure the reload yield behavior, and examined in the transmission electron microscope (TEM) to study the substructure evolution. The substructure and yield strength of the bulk shock-loaded copper samples were found to depend on the amount of e, in the shock-recovered sample at a constant peak pressure and pulse duration. In Fig. 6.8 the quasi-static reload yield strength of the 10 GPa shock-loaded copper is observed to increase with increasing residual sample strain. 

MW and MWD are very significant parameters in determining the end use performance of polymers. However, difficulty arises in ascertaining the structural properties relationship, especially for the crystalline polymers, due to the interdependent variables, i.e., crystallinity, orientation, crystal structure, processing conditions, etc., which are influenced by MW and MWD of the material. The presence of chain branches and their distribution in PE cause further complications in establishing this correlation. 

An in-depth understanding of structure-property relationships is perhaps the most important concern for the urethane formulation chemist. Material design objectives often go far beyond physical property requirements and may also include considerations like processing characteristics (i.e., compatibility, reactivity,... 

Singh [238] has recently reviewed emerging ultrasonic techniques for process sensing and control in manufacturing (for structure-property relationships), such as... 

In order to identify tyrosine derivatives that would lead to polymers that are processible, mechanically strong, and also biocompatible, we initiated a detailed investigation of the structure-property relationships in polyiminocarbonates and polycarbonates. Since the amino and carboxylic acid groups of tyrosine dipeptide (the N and C termini) provide convenient attachment points, selected pendent chains can be used to modify the overall properties of the polymers. This is an important structural feature of tyrosine dipcptide derived polymers. 

This book focuses on the relationships between the chemical structure and the related physical characteristics of plastics, which determine appropriate material selection, design, and processing of plastic parts. The book also contains an in-depth presentation of the structure-property relationships of a wide range of plastics, including thermoplastics, thermosets, elastomers, and blends. 

The crystallization kinetics of commercial polyolefins is to a large extent determined by the chain microstructure [58-60]. The kinetics and the regime [60] of the crystallization process determine not only the crystalline content, but also the structure of the interfaces of the polymer crystals (see also Chapter 7). This has a direct bearing on the mechanical properties like the modulus, toughness, and other end use properties of the polymer in fabricated items such as impact resistance and tear resistance. Such structure-property relationships are particularly important for polymers with high commercial importance in terms of the shear tonnage of polymer produced globally, like polyethylene and polyethylene-based copolymers. It is seen that in the case of LLDPE, which is... 

The measurement of rheological properties of the PLFNCs in the molten state is crucial in order to gain a fundamental understanding of the nature of the processability and the structure-property relationships for these materials. 

Riva, M., Campolongo, S., Avitabile Leva, A., Torreggiani, D., and Maestrelli, A. 2002. Structure-property relationships in osmo-air-dehydrated apricot cubes. In Book of Abstracts Symposium Drying, Processes, Structure and Functionality (IberDESH 2002) , pp. 103-104. Universidad Politecnica de Valencia, Valencia, Spain. 

Very recently we8 reported on a class of processable heavily fluorinated acrylic resins that exhibit dielectric constants as low as 2.10, very close to the minimum known values. In this chapter we report on the preparation of a series of processable heavily fluorinated acrylic and methacrylic homo- and copolymers that exhibit dielectric constants as low as 2.06, and the factors that affect the reduction of dielectric constant from structure-property relationships is elucidated.9... 

Pollutants with high VP tend to concentrate more in the vapor phase as compared to soil or water. Therefore, VP is a key physicochemical property essential for the assessment of chemical distribution in the environment. This property is also used in the design of various chemical engineering processes [49]. Additionally, VP can be used for the estimation of other important physicochemical properties. For example, one can calculate Henry s law constant, soil sorption coefficient, and partition coefficient from VP and aqueous solubility. We were therefore interested to model this important physicochemical property using quantitative structure-property relationships (QSPRs) based on calculated molecular descriptors [27]. 

In 1934 Paul Flory was hired to work with Carothers to help gain a mathematical understanding of the polymerization process and relationships. Thus, there was an early association between theory and practice or structure-property relationships. 

Therefore, polymer libraries, in combination with high-throughput screening techniques, are highly useful tools for the evaluation of (quantitative) structure-property relationships and/or the identification of hits of certain desired properties of the evaluated materials. These tools help researchers to understand their research problems more thoroughly by, e.g., finding optimal process conditions or product performance within a reduced amount of time and/or experimental effort. 

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