Naida A. Orientation modification in the manufacture of polyvinyl chloride pressure pipe

The thesis is concerned with creation of domestic technology and equipment for production of oriented PVC pipes, researching and implementing into industrial production. Developed technological basis for the creation of composite materials based on unplasticized polyvinyl chloride for oriented PVC-O pipes. Used new formulation of compositions based on unplasticized PVC at different technological parameters of mixing components of the composition, the introduction of additional technological additives, research into their influence on physical-mechanical and operational properties and characteristics of PVC-O pipes. Justified the use of discrete method of producing made of PVC-O pipes, as one that will allow to explore the necessary parameters of the workpiece of PVC-O formulations for PVC-O pipe. Conducted studies that showed the effectiveness of the selection of the formulation composition manufacturing of PVC pipes, selection of technological parameters of its production that will allow to obtain a pipe with improved physical-mechanical parameters and cheaper than pipe made from PVC. Created industrial equipment for manufacturing PVC-O pipes, optimal technological parameters of production of PVC-O pipes have been selected and substantiated. The results of the analysis of scientific literature and patent have been done. Considered issues of more efficient use of natural physico-chemical properties of polymers, which are depended as of the chemical nature of the original monomers so of their differential integrated changes in the polymer chains and the interaction of the latter in supramolecular formations, from the raw material base for the synthesis of PVC, ingredients on the basis of PVC; the prospects for extending the use of use of pipes made of oriented unplasticized PVC for water supply, including transportation of drinking water, other liquids. Analyzed possible methods of modification of properties and characteristics of products from PVC, reality of orientation of amorphous polymers and its dependence on the peculiarities of their configuration and conformation of the spatial structure. Methods of implementation of the orientation modifications, their justification have been done. Justified the possibility of modifying the amorphous polyvinylchloride in the composition by orientation in the manufacture of pipes by extrusion. Justified separate (one-step) method of the orientation of the workpiece pipes from unplasticized PVC. Showed the advantages of PVC-O pipes. Developed the technology of separate single-stage production of oriented pipes made of polyvinyl chloride, which consists of the following local technologies: -continuous extrusion technology for the processing of powdery PVC composition to unoriented pipe; -technology of cutting unoriented pipe on pieces for one-step orientation; - technology of one-step orientation of PVC in the longitudinal and radial directions; - technology of thermal stabilization of oriented PVC in the pipe body; -technology of manufacturing belling parts in the PVC-O pipe. Experimentally established the basic technological modes of receiving PVC-O pipes, including the modes of preparation of the mixtures of the PVC-O compositions; modes of extrusion, modes of single-stage orientation of PVC pieces of the pipe; the modes of thermal stabilization of PVC in the pipe body; the modes of manufacturing belling parts in the PVC-O pipe. Compared of physico-mechanical and operational characteristics of pipes made from UPVC and modified orientation PVC-O pipes.