Polychloroprene rubber 1.23 0000125957 00000 n 0000148052 00000 n Science based targets for a Global Plastics Treaty, Plastics For Change is now an Ocean Bound Plastic certified collector, efforts made by the plastic industry to increase its reusability, market is forecasted to grow even more in the following years, For Brands - Click Here to Source with Purpose. In addition, polystyrene is not accepted incurbside collectionrecycling programs and is not separated and recycled where it is accepted. The American Society for Testing and Materials (ASTM) is an organization that defines and sets standards to ensure good quality and workmanship. Available in a range of sizes these trays have many industrial uses. That value must be known in order to determine the overall weight of said project and whether its other components will be able to support the heft of the plastic component - which is why we've put together this quick and easy guide on the weights of some of our most popular plastics. Economics Engineering Enabling you to identify and mitigate the intrinsic risk in your operations, supply chains and business processes. Whether your business is local or global, we can help to ensure that your products meet quality, health, environmental, safety, and social accountability standards for virtually any market around the world. Machine Design Apps Mechanical Tolerances Specs Polysulphone 1.24 0000015048 00000 n
Vivak Sheet has become a staple in the point-of-purchase industry due to its economic advantages compared to polycarbonate and superior impact strength over acrylic. View Cart. Strength of Materials The tests for density and SG are particularly significant in the custom sheet industry because plastic sheet is sold on a cost per pound basis. Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with the amazing, fun and free SketchUp Make and SketchUp Pro .Add the Engineering ToolBox extension to your SketchUp from the SketchUp Pro Sketchup Extension Warehouse! Learn More, Validating the specifications, value and safety of your raw materials, products and assets. Civil Engineering Portions throughout the same sample may also differ in density due to differences in crystallinity, thermal history, porosity, or changes to the material composition, such as the addition of a filler or pigment. Gravity: Viscosity CPS 0000151051 00000 n 10XX,52,11XX,17,12XX,7,13XX,4,15XX,16,3XXX,2,40XX,10,41XX,12,43XX,5,44XX,4,46XX,5,47XX,3,48XX,3,5XXX,23,6XXX,3,71XX,1,8XXX,22,92XX,5,93XX,1,94XX,4,98XX,2,AISI,66,ASTM,172,Atomic-Mass,327,Atomic-Number,436,Atomic-Radius,86,Atomic-Symbol,329,Atomic-Volume,94,Austenitic,56,Boiling-Point,94,bp1,97,CBS,6,Chemical-Elements,100,Chemical-Symbol,217,CMDS,13,Coefficient-of-Thermal-Expansion,85,Covalent-Radius,87,Crystal-Structure,109,CS,17,CVS,3,Density,297,Duplex,6,el1,100,Elastic-Modulus,30,Electrical-Conductivity,79,Electro-Affinity,87,Electron-Configuration,109,Electronegativity,102,Electrons-per-Shell,111,Enthalpy-of-Fusion,93,Enthalpy-of-Vaporization,95,Ferritic,12,fp1,38,fs1,45,Group-Number,218,HCS,14,Heat-of-Fusion,87,Heat-of-Vaporization,85,HMCS,16,Ionic-Radius,78,Ionization-Energy,102,Ionization-Potential,101,l1,438,LCS,21,List,281,lp1,69,Martensitic,6,MCS,17,MDS,14,Melting-Point,96,mm1,2,mp1,99,MS,4,NCMDBS,6,NCMDS,31,NCS,2,NMDS,8,Oxidation-States,104,p1,44,Period-Number,107,pr1,53,Properties,40,RCLS,1,RCS,16,ref1,5,RRCLS,3,RRCS,4,SAE,201,Site,2,SMS,5,Specific-Gravity,83,Specific-Heat,92,Specific-Weight,1,SS,80,Tests,2,Thermal-Conductivity,105,tm1,274,Valence-Electrons,98,wt1,26, Materials: 2022: Specific Gravity of Plastic (& Formula, Definition, Infographic), 2022: Specific Gravity of Plastic (& Formula, Definition, Infographic), https://1.bp.blogspot.com/-qPMKZ48g6Vg/XRPSAE54r4I/AAAAAAAAOsY/VpY75KLZ6O4JJdZeUM1jyrM_g0N8xDB3QCLcBGAs/s320/specific-gravity-of%2Bplastic.webp, https://1.bp.blogspot.com/-qPMKZ48g6Vg/XRPSAE54r4I/AAAAAAAAOsY/VpY75KLZ6O4JJdZeUM1jyrM_g0N8xDB3QCLcBGAs/s72-c/specific-gravity-of%2Bplastic.webp, https://materials.gelsonluz.com/2019/07/specific-gravity-of-plastic-formula.html, Not found any post match with your request, STEP 2: Click the link on your social network, Can not copy the codes / texts, please press [CTRL]+[C] (or CMD+C with Mac) to copy, CBSE Class 10 Chemistry Chapter 2 Important Questions and Answers. Polyethylene terephtalate 1.34-1.39 This may also be referred to as relative density. or in connection with, the use of this information. or damage, or any loss or damage whatsoever arising from loss of materials, time or profits arising out of, 0000135948 00000 n And The SI unit is Kg/m3. WebSpecific Gravity (SG) is defined as the ratio of density of the material to the density of water (1 g/cm3) at a specified temperature. in various applications. Polymethylpentene 0.83 0000124911 00000 n 0000014816 00000 n One of the most basic differences between varieties, however, can be found in how much they weigh. 0000169321 00000 n More frequently, however, anything over 1.53 is called high-index. Heat Transfer It is mostly used for food and drink packaging purposes due to its strong ability to prevent oxygen from getting in and spoiling the product inside. In order to help you make better-informed decisions about the products that you buy, today we will go through the seven different types of plastic, how they differ, and their impact on the environment. From here density and SG are calculated using the following formulas: Specific Gravity = (Weight A / Weight B)Density = (Weight A / Weight B) * 0.9976 g/cm3 , where 0.9976 g/cm3 is equal to the density of distilled water at 23C. Impact Consumer Products Group All Rights Reserved 2023, 5 Highland Drive Because of this difference, when comparing polypropylene sheet to PET sheet, holding constant gauge and size, customers can see approximately a 30% density reduction from PET to PP and an increased yield on pounds purchased. SPECIFIC GRAVITY- The ratio of the weight of 0000132332 00000 n The best-known plastics of this group are polycarbonates(PC) used to build strong,toughproducts. Therefore, the specific gravity (which is dimensionless) for a liquid has the same numerical value as its density in units of g/cm3. Others might see it as an important way to reduce risk or liability. Polyethylene It has the simplest structure of all the plastics, making it easy and cheap to produce. LDPE 0.91-0.93 Animals do not recognize it as artificial and may mistake it for food causing serious effects on the health of birds or marine animals that might swallow it. dixonvalve.com. 0000153750 00000 n Do you have a packaging idea and need some guidance on which material is best? 0000011164 00000 n Engineering Standards Specially designed for marine applications, antiskid HDPE sheeting offers superior durability with the additional benefit of a non-skid surface perfect for high-traffic marine surfaces. 0000166558 00000 n
Expanded PVC sheet plastic is the ideal material where durable construction materials are needed. Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications! 0000138434 00000 n We carry a large selection of American-made Tamco industrial strength tanks. When mixed with other substances, It can be made softer and more flexible and applied to plumbing, wiring, and electrical cable insulation and flooring. 6I&dsV.G{w+Z#Ot>wY[~JKWr#oyOIIl(RV[U|i:n0qfB#}CNs,%|PEyeTeB 0000131261 00000 n Thermodynamics Directory | Heat Transfer Directory, Specific Gravity Table Chart and Equation. The member-related functions have been closed due to the deactivation of cookies. 0000005721 00000 n 0000012608 00000 n I'm Gelson Luz, mechanical engineer, welding specialist and passionate about: I am building this blog to be the best learning blog about engineering! You have no items in your cart. ), Copyright 2000 - Technical name - High-Density Polyethylene its an incredible resistant resin used for grocery bags, milk jugs, recycling bins, agricultural pipe, but also playground equipment, lids, and shampoo bottles among others. For more information Please review the privacy policy, Disabling cookies will make it impossible to use member-related functions. So youve narrowed down what material you need thanks to our Learn More About your Plastic Sheet series - now its time to download a data sheet and take a look at the performance attributes of our materials. Cookies are only used in the browser to improve user experience. 0000127802 00000 n WebPURPOSE: The title filler having a low specific gravity and excellent affinity for plastics and retention of electric conductivity, prepared by applying a metallic coating to the surface of an isotactic polyolefin powder or particle etched in the presence of a specified chemical agent. We don't save this data. 0000005504 00000 n Plastics Synthetics ?b0/7>41"FUm'V69mjqQn[pd@,XrKC^k $e-eI]abs6QCoq$Y+4Gb=.bsm?JBny!Q.h38'!xSi{C ,*+R9hHz Total elongation at failure of some polymers: Tensile modulus or Young's Modulus is the ratio of stress to strain within the elastic region of the stress-strain curve before the yield point. WebSince the density of a fluid varies with temperature, specific gravities must be determined and specified at particular temperatures. The solid wood density may be determined using the green volume, The specific gravity of a substance is a comparison of its density to that of water. Polyacronitrile 1.17 Therefore, for the same 1cm volume, the melted plastic weighs less than the solid plastic (0.933 g/cm vs. 1.054 g/cm). Learn More, Density and Specific Gravity ASTM D792, ISO 1183, K-SHOW:Visit us at K2022: Supporting Polymers and Materials Development, NEW SERVICE:CircularAssure - Services to help you close the loop in the circular economy for plastics, ARTICLE:Processability and evaluation programmes for recycled plastic materials, ARTICLE:Adhesives Quality Assurance Testing Programs, ARTICLE:Enabling Polymer Non-Wovens Development, CASE STUDY:Polymer Surface Contamination Resolution, CASE STUDY:Polymer Failure - Distribution and Dispersion of Fillers, Ensuring the Safety and Performance of Electrical Products, Testlopedia - The Plastics Testing Encyclopedia, Plastics Circular Economy Solutions - CircularAssure, Physical and Mechanical Testing of Polymers, Thermal Analysis of Polymers and Plastics, Polymer Regulatory and Consulting Services, Polymer Product Processing Development Support, Microbeads and Microplastics Testing and Consultancy, Coatings and Thin Films Analysis and Testing, Supporting Polymers and Materials Development, Processability and evaluation programmes for recycled plastic materials, Adhesives Quality Assurance Testing Programs, Polymer Failure - Distribution and Dispersion of Fillers. (You will help other colleagues find this blog). A Specific Gravity of less than 1 means that the You can target the Engineering ToolBox by using AdWords Managed Placements. In the next blog post, we will explain which of these plastic types can be recycled and which not, so stick around! Specific gravity, generally speaking, measures the density of an object as compared to water. 0000005093 00000 n Polybutene 0.91-0.92 Because its made with long unbranched polymer chains its much stronger and thicker than PET. As far as its disposal is concerned, HDPEis accepted at mostrecyclingcenters in the world, as it is one of the easiest plastic polymers torecycle. 0000161897 00000 n ph20 = density of water, standarized at temperature 4C (kg/m3), (Samples may vary, and these figures are approximate. Web1 28768 DENSITY OF PLASTICS What is Density of plastic: The density of a substances is generally known as mass per unit volume. This site requires JavaScript to function. Ethylene-propylene 0.86 +hSm)/BNy-G:ipb4m(5i9 18N 2Y9 E7q!#5qnc"w2T.Cz(k4l@Ar$.n(*piE1uh%UF?x]*t4\J4j1i,/7Mq$``'> How about an incentive to share this post? WebSpecific Gravity Information. Downloads Example: A gallon of oil weighs 9.5 lbs per gallon9.5 lbs / 8 = 1.187 specific gravity. One of the most commonly used plastics, our heavy duty acrylonitrile butadiene styrene, or ABS sheeting, has a high impact resistance and durability to be used for automotive, printing, and display applications. Electronics Instrumentation 0000142018 00000 n 0000167357 00000 n Method A is the more common test method used, and can be performed with sheet, rod, tube and molded pieces of plastic materials that are not affected by water. Lubrication Data Apps On top of this, plastics number 7 is almost never recycled. Description: This 3/8" OD x .062" Wall Yellow Polyethylene Tubing has a working pressure of 120 PSI @ 72F. LLDPE 0.91-0.94 Since then, after undergoing some minor variations, the RIC has been recognized as the worldwide standard plastic classification. 0000137613 00000 n Environmentally-speaking its among the worst types of plastic: first, it is regarded as notbiodegradable. Electric Motor Alternators Training Online Engineering. WebThough some manufacturers use grams per cubic centimeter to indicate the weight of their products, others merely provide the specific gravity of their material. 0000125208 00000 n WebMaterial density g/cc 1 g/cc = material density = specific gravity Therefore, knowing the specific gravity and with the help of the handy conversion table on the shared drive one To sum up, its a no-go. For example, The American Society for Testing and Materials (ASTM), approximately a 30% density reduction from PET to PP and an increased yield on pounds purchased.
. 0000004768 00000 n Since the density of a fluid varies with temperature, specific gravities must be determined and specified at particular temperatures. can be special ordered. Phone: 860-963-1976 First, we have to know that the formula of density is: As formula shown, density is total mass of the object divided by total volume of object, which means: 1 gram per cubic centimetre or 1 kilogram per cubic metre.Density of water is1 gram per cubic centimeter (1 g/cm3), but actually, the exact density of water is not really 1 g/cm3, but rather a bit less (very, very little less) than 1, so we can say thatgenerally the weight and volume of water is the same.What's the meaning of "Specific Gravity"?Specific Gravity means specific value of an object undernormal temperature and pressure. HDPE 0.96-0.97 Section Properties Apps 0000117111 00000 n 0000003888 00000 n 0000002356 00000 n 1 gallon of water weighs 8.33 lbs. Therefore, the specific gravity is a unitless number. 0000175797 00000 n Polystyrene 1.05 If plastic cannot be identified in the six types above-mentioned, then it will be included in group number 7. Roto-molded LLDPE with thick walls for superior strength anddurability. 0000173991 00000 n 0000146514 00000 n Perhaps better known by its commercial name Styrofoam its highly inflammable and dangerous as it can leach harmful chemicals, especially when heated (which often happens because, as its found in disposable take-out containers, people oftentimes microwave it to heat up the food inside it). Structural Shapes 0000117341 00000 n One of the most remarkable features of plastic is just how greatly its features can vary from variety to variety. 0000005946 00000 n Materials with an index between 1.53 and 1.57 are sometimes considered mid-index, while 1.58 and greater is considered high-index. Other custom sizes of trays, special partitions, flanges, outlets, etc. It is common to use the 0000051762 00000 n With a smooth, matte finish, expanded PVC sheets provide the great surface for graphic overlays., Sign up for A&C Plastics Updates, Promotions. Urine normally has a specific gravity between 1.003 and 1.035. Not all plastic is born equal. ,unv . Also, it is relatively hard and resistant to impact and can be subjected to temperatures of up to 120 C without being affected. Specific gravity (S.G.) is a measure of the relative density of a substance as compared to the density of water at a standard temperature. Spring Design Apps Specific Gravity means specific value of an object under normal temperature and pressure. Specific gravity, The lower the density or SG of a particular material, the more material per pound or surface area you will get. Tensile yield strength is the maximum engineering stress in psi (or Pa) at which a permanent non-elastic deformation of the thermoplastic material begins. Polyvinyl chlorideis the world's third-most widely produced syntheticplasticpolymer. 0000149107 00000 n Plastic Corp. carries an excellent selection of spray bottles perfect for cleaning. 0000016671 00000 n 0000102892 00000 n Definition: Density v.s. WebDensity of Plastics Material: Technical Properties Table. ?qbC2]2F Specific Gravity Polystyrene is the sixth type of plastic on the list and it can be solid or foamed. +74|=8/[ dcepJ@@ Q endstream endobj 8 0 obj<> endobj 10 0 obj<> endobj 11 0 obj<>/Font<>/XObject<>/ProcSet[/PDF/Text/ImageB/ImageC/ImageI]>> endobj 12 0 obj[278 750 474 750 750 750 750 238 750 750 750 750 278 750 278 278 556 556 556 556 556 750 750 750 556 750 750 750 750 750 750 611 750 722 750 722 722 667 611 778 722 278 750 750 750 750 722 778 667 750 722 667 611 750 667 944 750 667 750 750 750 750 750 750 750 556 611 556 750 556 333 611 750 278 750 750 278 750 611 611 611 750 389 556 333 611 556 750 556 556] endobj 13 0 obj<> endobj 14 0 obj<> endobj 15 0 obj<> endobj 16 0 obj<> endobj 17 0 obj<> endobj 18 0 obj[/ICCBased 39 0 R] endobj 19 0 obj[278 750 355 750 750 750 750 191 333 333 389 750 278 333 278 278 556 556 556 556 556 556 556 556 556 556 278 750 750 584 750 556 750 667 667 722 722 667 611 750 722 278 750 667 556 833 722 778 667 750 722 667 611 722 667 944 750 750 750 750 750 750 750 750 750 556 556 500 556 556 278 556 556 222 222 500 222 833 556 556 556 556 333 500 278 556 500 722 500 500] endobj 20 0 obj<> endobj 21 0 obj<> endobj 22 0 obj[278 750 750 750 750 750 750 750 333 333 750 750 750 750 278 278 750 750 750 750 750 750 750 750 750 750 750 750 750 750 750 750 750 750 750 750 722 750 750 750 750 750 750 750 750 750 750 750 750 750 750 750 750 750 750 750 750 750 750 750 750 750 750 750 750 556 750 500 556 556 278 556 556 222 750 750 222 833 556 556 556 750 333 500 278 556 500 750 750 500] endobj 23 0 obj[250 778 778 778 778 778 778 778 778 778 778 778 778 778 778 778 778 500 500 778 778 778 778 778 778 778 778 778 778 778 778 778 778 778 778 667 778 778 778 778 778 778 778 778 778 778 778 778 778 778 778 778 778 778 778 778 778 722 778 778 778 778 778 778 778 444 500 444 500 444 778 778 778 278 778 778 278 778 500 500 778 778 333 389 278 778 500] endobj 24 0 obj<> endobj 25 0 obj<> endobj 26 0 obj<>stream 3t6/8lM2-lA Please read Google Privacy & Terms for more information about how you can control adserving and the information collected. Intertek is the industry leader with employees in 1,000 locations in over 100 countries. Density of Plastics: Technical Properties. Density measures the mass per unit volume. It is calculated by dividing the mass of the material by the volume and is normally expressed in g/cm 3. The density of a plastic sample may change due to change in crystallinity, loss of plasticizers, absorption of solvent, etc. The standard test method for the determination of density and specific gravity 0000165724 00000 n 0000004599 00000 n 0000176664 00000 n Web800.789.1718. In fact, PET bottles arethe most widelyrecycled plasticin the world! This changes the ratio for our calculation; it is now 0.945/0.74 or 1.28. Beam Deflections and Stress For PS the melt density is 0.945 g/cm 3 and for PP it is about 0.74 g/cm 3. Engineering Forum Vibration Engineering One of the ASTM test methods for plastic commonly seen on data sheets is the test for Density and Specific Gravity (SG). The difference of Density & Specific Gravity. Cleaning & Industrial U.S. xb```f`g`g`0cb@ !V6C'``D&yY(J-Ftt@UJ `H Dvp48(kha``aAA8koxD(lb'ftb~ef.aS-`0`"#a(1&' .8ffgS D!f' 0000015222 00000 n Styrene-butadiene 0.93 0000143715 00000 n 0000133447 00000 n Specific Gravity (SG) is defined as the ratio of Solids and Metals - Specific Gravities . Specific gravity for some common solids and metals like aluminum, asbestos, brass, calcium and many others . Sponsored Links . The Specific Gravity - SG- is a dimensionless unit defined as the ratio of density of the material to the density of water at a specified temperature. In 1988, theSociety of the Plastics Industryintroduced the Resin Identification Code (RIC) system which divided plastic resins into 7 different categories. This website uses cookies to collect necessary user browsing behaviors so that we can provide you with a better browsing experience. In fact, not only can plastic be found in a variety of different shapes and colors, but also in many different types. 0000124655 00000 n WebSimply enter the density of the material in which your are interested, select the shape from the drop-down list, enter the dimensions, then hit the Calculate button. Welding Stress Calculations This test is often seen with the designation ASTM D792. Heres a brief recap of what we have learned so far: We hope this blog post has provided some clarity about the differences among all these plastic types. Polyvinyl acetate 1.19 Polycarbonate 1.2 Flat Plate Stress Calcs 0000164707 00000 n PA-66 1.13-1.15 Hard and sturdy, it can withstand high temperatures and is found in tupperwares, car parts, thermal vests, yogurt containers, and even disposable diapers. 1, Zhongshan Rd., Dacun Township, Changhua County 515, Taiwan (R.O.C. Web most plastic baby bottles 5-gallon water bottles sport water bottles metal food can liners clear plastic sippy cups some clear plastic cutlery Mixed resin plastics like #7 are difficult, if not impossible, to recycle. Yield point is the first point where the specimen yields, where the specimen's cross-sectional area begins to contract significantly, or where the strain can increase without increase in the stress. PA-6 1.12-1.13 There are two basic test procedures to determine the density of a material method A, used for testing solid plastics in water, and method B, used for testing solid plastics in a liquid other than water. 0000156682 00000 n 0000142860 00000 n Should reactivate cookies? Plastic (CR-39) and Crown Glass are considered base index with indices of 1.498 and 1.52 respectively. 0000008409 00000 n 0000171239 00000 n 0000173123 00000 n Each one is different from the other and has different uses. General Fax: 860-963-1998, Understanding Your Data Sheet: Density & Specific Gravity, So youve narrowed down what material you need thanks to our. 0000139528 00000 n Helium gas has a density of 0.164g/liter It is 0.139 times as dense as air . "Density" has its own unit of measurement, 1 g/cm3 or 1 kg/m3, in contrast, specific gravity has no unit of measurement goes with it; nevertheless, although they don't have the same meaning, they have the same value because density of water is quite close to 1g/cm3. 0000174998 00000 n However, various factors can affect density such as crystallinity, loss of plasticizer or absorption of solvent. %PDF-1.4 % Density refers to the mass per unit volume of a material, whereas SG refers to a measure of the ratio of mass of a given volume of material at 23C to the same volume of deionized water. Second, polystyrene foam blows in the wind and floats on water, due to its low specific gravity. 0000151915 00000 n But they can also be found on mobile phones and, more frequently, in compact-discs (CD). Please read AddThis Privacy for more information. It is a very inexpensive resin per unit weight and easy to create, for these reasons it can be found everywhere: from beverage cups, insulation, packing materials to egg cartons and disposable dinnerware. WebThe Specific Gravity - SG- is a dimensionless unit defined as the ratio of density of the material to the density of water at a specified temperature. 0000124088 00000 n POM 1.41-1.43 Fluid. Polymers typically have a benchmark density that can offer an approximate value of what the density of a particular material can be expected to be. In its rigid form, PVC is largely used in the building and construction industry to produce door and window profiles and pipes (drinking and wastewater). | Contact, Home Specific gravity is the ratio of the object's density to the density of water, i.e. Plastics have a really wide specific gravity range depending on its composition. 0000018128 00000 n Hi! 0000006910 00000 n 2023 Ji-Horng Plastic Co., Ltd. All rights reserved. the molded piece as compared to the weight of an equal volume of water Its usually picked up through most curbside recycling programs and has a tremendously positive track record! United States Plastic Corp. and while we endeavor to keep the information up to date and correct, we make no representations or In recent years, the use of these resins has been controversial: the basis of this controversy is their leaching that, occurring at high temperature, releasesbisphenol A, a compound that is on the list of potential environmental hazardous chemicals. WebSpecific gravity is a measure of the ratio of mass of a given volume of material at 23C to the same volume of deionized water. 0000126937 00000 n Typical properties of some common thermoplastics: For full table with Thermal Conductivity, Specific Heat and Maximum Temperature Limit - rotate the screen! Our Polycarbonate sheet offers a levelof safety that no other clear glazing material can match. 0000004435 00000 n Beverage bottles are among the main plastic items that come for PET. If you are interested in knowing more about what we do, click here. 0000158889 00000 n 0000136804 00000 n Acrylic doesn't have as much impact resistance as polycarbonate; polycarbonate's tensile strength is greater than that of PVC; PVC's heat deflection abilities are lesser than Vivak's; and so on, and so on. WebSpecific gravity is the (unit less) ratio of the solid wood density to the density of water at the same temperature. Specific gravity of a material can be calculated by following equation: The testing method of SG for plastic systems is ASTM D792 and ISO 1183. SG of plastic is less compared to other materials influence its price; thus all plastic materials are sold on cost per weight basis. 9;-h3UR{SD bD=NSH3)0lefD}n 81 c+0!o XFu#N/? Used in plastic bags,six-pack rings, various containers, dispensing bottles, and most famously for plastic wraps, is not often recycled through curbside programs. The specific gravity of plastic is the ratio of the density of plastic to that of a reference substance (Usually water).