Introduction
\nThey were developed in the mid-19th century.
\nUntil the mid-1950s, the main source of raw material for the plastics industry in Europe was coal.
\nToday, the plastics industry is closely related to the oil industry. The reason is the development of petrochemical and oil industries and changes in human consumption patterns.
\nWidely used, from common items (bottles, bags, etc.) to technology (electronics, aerospace, etc.)
\nProduction of more than 150 million tons annually in the world
\nOne of the best human artifacts and the main environmental pollutants
\nPlastic is considered a non-degradable material with a lifespan of about 500-300 years. Plastic waste left over from food products, which is used as food and hygiene packaging, is a major problem. The most obvious of these are visual and environmental pollution and irreparable damage to water, soil, air and living organisms.
\nThe raw materials for making plastics are polymers.<\/p>\n
Polymer + additives = plastics + processing = plastic objects + utilization = plastic waste<\/p>\n
\nPolimer (Greek) = \u0628\u0633\u067e\u0627\u0631 (Persian)
\nPolymers: from the connection of one or more monomers with long chains of carbon and hydrogen
\nPolymers are linear, branched, cross-linked according to their reaction.
\nTypes of polymers
\nHomopolymer
\nCopolymer
\nNatural polymers: polynucleotides, polysaccharides, polypeptides
\nSynthetic polymers: synthetic rubbers, bakelites, nylons, polyesters
\nSynthesis of polymers: laboratory, biological and modified natural polymers
\nLaboratory synthesis
\nAdditional polymerization: polyethylene, chipboard, polyvinyl chloride
\nCondensation polymerization: nylon (polyamide), Dacron, Kevlar
\nProperties of polymers
\nPolymer strength
\nIncrease in the boiling, melting and viscosity points of the polymer with increasing chain length
\nIncrease in elastic strength
\nHigh strength of polymers due to their crystalline structure
\nHigh dyeability
\nTypes of polymers
\nThermoplastic (soft heat)
\nCan be liquefied by heat – they are malleable and can be used after cooling. Such as: polyethylene, polypropylene, polyvinyl chloride, polystyrene<\/p>\n
They do not melt and burn and are destroyed after a while when heated. Such as: phenol formaldehyde, urea formaldehyde, epoxy resins, unsaturated polyesters, polyurethanes, polyacetals, polyamides, polycarbonates<\/p>\n
PVCis a member of the family of polymers and copolymers, has a common vinyl group -CH2-CH<\/p>\n
60% of PVC is chlorine, which is obtained from table salt
\nIt has little transparency, but due to the bulky polymer chains (the result of the large substitution of chlorine), it has strength and hardness.<\/p>\n
\nUnder open air conditions, a colorless, flammable gas with a slightly sweet odor
\nHigh vapor pressure and relatively low solubility in water
\nLiquid under pressure
\nVery stable and non-corrosive at limited temperatures and in the absence of air, but decomposes somewhat at temperatures above 450 \u00b0 C and in the presence of sodium or potassium hydroxide
\nIn the United States, about 97% of VC is used to synthesize PVC, and the rest is used to produce copolymers, methyl chloroform and other uses
\nFormation of vinyl chloride polymers from vinyl chloride monomers<\/p>\n
\nPolystyrene is biologically neutral and transparent, has good resistance to water absorption, and is a very good thermal and electrical insulator. The main problem is contact with styrene<\/p>\n
monomers, and products such as formaldehyde, benzaldehyde, ammonia, carbon monoxide, etc. are also produced in thermal decomposition<\/p>\n
\nStyrene is commercially obtained by dehydrogenation of ethylbenzene Comes
\nStyrene is widely used in the production of polystyrene, plastics, polyesters, protective coatings and resins.
\nStyrene is a colorless to slightly yellowish, oily liquid with a pungent aromatic odor
\nIt is slightly soluble in water and soluble in alcohol, ether, acetone, benzene, carbon disulfide
\nStyrene is heavier than air and forms an explosive mixture in the range of 1.1 to 6.1% of air.<\/p>\n
Polyethylene is a polymer made from ethylene. Ethylene is the lightest olefin, a colorless, flammable gas with a slightly sweet odor<\/p>\n
Polyethylene resins have high flexibility, good resistance to acids, bases, and salts (except strong oxidizing agents) and water<\/p>\n
Three main groups of polyethylene: high-density polyethylene (HDPE), low-density polyethylene (LDPE), and linear low-density polyethylene<\/p>\n
High-density polyethylene: reduced flexibility, resistance to chemicals and environmental stresses<\/p>\n
Light-density polyethylene: low density and good flexibility<\/p>\n
Linear low-density polyethylene: better strength and elasticity, resistant to tearing and puncture<\/p>\n
\n
\nPolypropylene is a thermoplastic polymer, opaque, rigid, and resistant to heat, chemical solvents, bases, and acids<\/p>\n
One of the most important properties of polypropylene is its lack of moisture absorption, which makes it a It has become a suitable choice for many applications.
\nEase of molding for injection molding and acceptable fluidity in the mold
\nAbility to mix with fillers such as sawdust and create composites
\nAbility to heat weld
\nAbility to recycle<\/p>\n
\nPhthalates are widely used as plasticizers in PVC production
\nThe use of phthalates as an additive has been a concern in recent years due to the increase in cancer and liver damage.
\nAmong the more than 30 different phthalates available on the market: DEHP is the most widely used plasticizer
\nDEHP is clear and oily
\nWidely used in the production of plastic and PVC products manufactured in medical products, blood bags, surgical tubes, food coatings and children’s toys
\nDEHP can be medically challenging because significant amounts of it have been found in blood products, which can pose health risks due to<\/p>\n","protected":false},"excerpt":{"rendered":"
Introduction They were developed in the mid-19th century. Until the mid-1950s, the main source of raw material for the plastics industry in Europe was coal. Today, the plastics industry is closely related to the oil industry. The reason is the development of petrochemical and oil industries and changes in human consumption patterns. Widely used, from […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8],"tags":[14,29],"class_list":["post-299","post","type-post","status-publish","format-standard","hentry","category-8","tag-14","tag-29"],"_links":{"self":[{"href":"https:\/\/pipeethylene.com\/en\/wp-json\/wp\/v2\/posts\/299","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pipeethylene.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/pipeethylene.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/pipeethylene.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/pipeethylene.com\/en\/wp-json\/wp\/v2\/comments?post=299"}],"version-history":[{"count":3,"href":"https:\/\/pipeethylene.com\/en\/wp-json\/wp\/v2\/posts\/299\/revisions"}],"predecessor-version":[{"id":886,"href":"https:\/\/pipeethylene.com\/en\/wp-json\/wp\/v2\/posts\/299\/revisions\/886"}],"wp:attachment":[{"href":"https:\/\/pipeethylene.com\/en\/wp-json\/wp\/v2\/media?parent=299"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/pipeethylene.com\/en\/wp-json\/wp\/v2\/categories?post=299"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/pipeethylene.com\/en\/wp-json\/wp\/v2\/tags?post=299"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}