Fire-Resist Bio-Based Polyurethane for Structural Foam Application

Polymer melts (or polymer solutions) with a solubilized gaseous component (which occur under sufficiently high pressures, thus forming homogeneous mixtures), and polymer melts (or polymer solutions) with dispersed gas bubbles (thus forming heterogeneous mixtures of polymeric fluid and gas bubbles) are encountered in thermoplastic foam processing and polymer devolatilization. Thus, a good understanding of the rheological behavior of such mixtures is very important to the design of processing equipment and successful optimization of such polymer processing operations. From the 1950s through the 1970s, the dynamics of a single, spherical gas bubble dispersed in a stationary Newtonian or viscoelastic medium was extensively reported in the literature (Barlow and Langlois 1962; Duda and Vrentas 1969; Epstein and Plesset 1950; Folger and Goddard 1970; Marique and Houghton 1962; Plessst and Zwick 1952; Rosner and Epstein 1972; Ruckenstein and Davis 1970; Scriven 1959; Street 1968; Street et al. 1971; Tanasawa and Yang 1970; Ting 1975; Yang and Yeh 1966; Yoo and Han 1982; Zana and Leal 1975). While such investigations are of fundamental importance in their own right, they are not much help to describe bubble dynamics in thermoplastic foam extrusion or structural foam injection molding, for instance. There is no question that an investigation of bubble dynamics in a flowing molten polymer with dispersed gas bubbles is a very difficult subject by any measure. Thus, understandably, a relatively small number of research publications on bubble dynamics in a flowing molten polymer have been reported (Han and Villamizar 1978; Han et al. 1976; Yoo and Han 1981). The complexity of the problem arises from other related issues, such as the solubility and diffusivity of gaseous component(s) in a flowing molten polymer, which in turn depend on temperature and pressure of the system. Further, a gaseous component solubilized in molten polymer in the upstream side of a die, for instance, may nucleate as the pressure of the fluid stream decreases along the die axis, after which they could grow continuously as the molten polymer with dispersed gas bubbles flows through the rest of the die.

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Resource-Saving Technologies in the Thermal Insulation-Structural Foam Glass Production

Materials Science Forum ◽

10.4028/www.scientific.net/msf.974.356 ◽

2019 ◽

Vol 974 ◽

pp. 356-361

Author(s):

O.V. Kuznetsova ◽

N.D. Yatsenko ◽

A.I. Subbotin ◽

M.Yu. Klimenko

Keyword(s):

Building Materials ◽

Raw Materials ◽

Foam Glass ◽

Scientific Research ◽

Glass Production ◽

Environmental Safety ◽

Resource Saving ◽

Structural Foam ◽

Safety Requirements ◽

Research Areas

The modern building materials market places high demands on heat-insulating and heat-insulating structural materials. In this connection, the issues of developing high-quality building materials obtained on the resource-saving technologies basis allowing to solve two interrelated problems are topical. The first problem is the industrial waste generated and existing stocks disposal. The second is associated with a decrease in the traditional raw materials deficit [1]. These problems solution, combining rational technological solutions, is based on the scientific research achievements in this area, in particular in the foam glass production. The priority scientific research areas in the foam glass materials production are the developments related to the study, the new raw materials use and the production of foam glass mixture compositions on their basis, which provide, along with the necessary performance properties, high environmental safety requirements [2, 3].

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