All you need to do to show any repeat unit is break the double bond, show where new bonds will form if the molecule reacts with another monomer and then put a bracket around that part. HashLearn is India's first on-demand tutoring app. Join. More complex repeat units can occur in vinyl polymers -[CH2-CHR]n-, if one hydrogen in the ethylene repeat unit is substituted by a larger fragment R. Polypropylene -[CH2-CH(CH3)]n- has the repeat unit -[CH2-CH(CH3)]. Polystyrene is a synthetic aromatic polymer made from the monomer styrene. Repeating Unit Of Polystyrene. D) 2.047 10 4 units. "Elements of Polymer Science and Engineering" (Academic Press 1982) p.3, "Glossary of basic terms in polymer science (IUPAC Recommendations 1996)", https://en.wikipedia.org/w/index.php?title=Repeat_unit&oldid=961970565, Creative Commons Attribution-ShareAlike License, This page was last edited on 11 June 2020, at 11:11. Given that the repeating unit in polystyrene is 104 and that the distance between the carbon- carbon bonds in the main chain is 1.54 A calculate the following: The mean-square end-to-end distance for a polystyrene molecule with the molecular weight 10° by assuming that the molecule behaves like a freely rotating, freely joined volumeless chain. In Reaction 5, since the double bond is in a different position (the C1 position), the polymer formed will have as its repeating unit a carbon atom with 2 hydrogen atoms attached, and a carbon atom with one hydrogen attached and a … C) 3.031 10 4 units. The repeating units are called monomers. Include All H Atoms. Draw The Monomer, Given That This Polymer Forms By Addition Polymerization. acid polyamide 6 (nylon 6) In the last example, where the synthesis reaction requires the alternate combination of two different monomers, the repeating unit is formed by two … i know the answer is 1.1515 x 10^4 but how is it? Compute the degree of polymerization for a polystyrene (PS) polymer with a number-average molecular weight of 260150 g/mol. Polystyrene is a synthetic aromatic polymer made from the monomer styrene. (Gowariker et al.,2009) Polystyrene is playing an important role in this modern life nowadays because of its efficiency, cost-effectiveness and lightweight. Answer to: The repeat unit in a polystyrene coffee cup has the formula C6H5CHCH2. A single molecule of polystryene has the repeating unit -[CH 2 CH(C 6 H 5)] n-, where n is the number of repeating units. Although we commonly like to draw the structure of polystyrene as the isotactic structure because it is easy to see the repeating units, in fact, when styrene monomers are polymerised very little of the resulting polystyrene is in the isotactic form. Solution (a) The repeat unit molecular weight of polystyrene is called for in this portion of the problem. Polystyrene. polystyrene and polypropylene are some examples of plastic in industry. The brackets contain the repeating unit. your own Pins on Pinterest (b) A simplified representation of polyvinyl acetate. 2501.0 . Here's an example: We notice that the repeating unit is linked to the rest of the chain by amide functional groups, and that the repeating unit contains an amide group. Condensation polymers: repeat unit and structural units, Rudin A. Transcribed Image Text 2 pts Question 13 The repeat unit of polystyrene, which has 8 carbon atoms, and 8 hydrogen atoms. What is the degree of polymerization?… A polystyrene-based resin foam body according to claim 8, wherein said polymer is selected from the group consisting of a homopolymer comprised of as a repeating unit acrylic acid, methacrylic acid or a derivative thereof; a copolymer comprised of as repeating unit acrylic acid, methacrylic acid or a derivative thereof; a copolymer comprised of as repeating unit vinyl alkylate; and a copolymer … n is usually between 2,000 and 100,000 units. (b) A simplified representation of polyvinyl acetate. constitutes the repeating units. The molecular mass of the chain is just the product nMR. The numbers preceding the poly prefix designate the first and last carbon atoms of the backbone repeating unit. Extruded polystyrene (XPS) is commonly used in architectural models. We connect students with top tutors from the IITs and BITS - instantly, anytime, anywhere. When drawing one, you need to: 2. Propene's polymer repeat unit will look something like this: ### CH3 ### |- … The numbers preceding the poly prefix designate the first and last carbon atoms of the backbone repeating unit. The incredible insulating capabilities of polystyrene can maintain the temperature hot or cold. (a) Compute the repeat unit molecular weight of polystyrene. It is a rather poor barrier to oxygen and water vapour and has a relatively low melting point. The condensation involves loss of water, as an H is lost from each HO- group in the glycol, and an OH from each HOOC- group in the acid. 552450.0 g/mol. how big … Bonus: Use your free doubt session & get a free formula book! A) Compute the repeat unit molecular weight of polystyrene. In this diagram the little "n" means that this group of atoms is repeated over and over to make the large polystyrene molecule … Attend recorded … Polystyrene is made from the monomer styrene which is a liquid petrochemical. Just enter your phone number below. polystyrene and polypropylene are some examples of plastic in industry. A collection of products made from polystyrene: a cup, a guitar case, polystyrene carvings, and floating pool noodles. The subscript "n" denotes the degree of polymerisation, that is, the number of units linked together. Rather, the structure of a polymer can be condensed and represented as shown in the figure below. The repeat unit is highlighted in blue. One repeat unit therefore has a molar mass of M(C 3H 6) = 42:08gmol 1. Polymer is a combination of small … Hydrogen is an explosive gas, oxygen supports combustion, why, when adding 2 hydrogen atoms to 1 oxygen atom, is the result an inert liquid? Chemistry; Thread starter AndrewDe; Start date Sep 27, 2017; Sep 27, 2017 #1 AndrewDe. Polystyrene. Answer with step by step detailed solutions to question from Arihant's BITSAT Prep Guide, Polymers- "Repeating unit of polystyrene is" plus 6299 more questions from Chemistry. M is the molecular weight of the polymer, DP is the degree of polymerization and the M 0 is the formula weight of the repeating unit. These two solvents are more water-like than hydrocarbon-like. Out of the total production of styrene, about 50% is used to produce polystyrene, about 20% to elastomers, polymer dispersions and thermosetting resins, 15% to produce ABS and SAN copolymers, 10% in expanded polystyrene (EPS), and the rest is for the production of various copolymers and specialty materials. A single molecule of polystryene has the repeating unit -[CH2CH(C6H5)]n-, where n is the number of repeating units. constitutes the repeating units. For example, in polyethylene terephthalate (PET or "polyester"), the repeat unit is -CO-C6H4-CO-O-CH2-CH2-O-. 14.4 (a) Compute the repeat unit molecular weight of polystyrene. The squiggly lines indicate that the polymer molecule extends further at both the left and right ends. M is the molecular weight of the polymer, DP is the degree of polymerization and the M 0 is the formula weight of the repeating unit. (b) Compute the number-average molecular weight for a polystyrene for which the degree of polymerization is 25,000. The polybutadiene is dissolved in styrene, which is then subjected to free-radical polymerization. Addition polymerization of an alkene. -[CH2-CHCl]n-, whose repeat unit is -[CH2-CHCl]-. Trending questions. The effect of nanoconfinement on the glass transition temperature (Tg) of supported polystyrene (PS) films is investigated over a broad molecular weight (MW) range of 5000−3 000 000 g/mol. Trending questions. repeating unit. HashLearn is the #1 platform to get online coaching for competitive exams. The repeating structural unit of most simple polymers not only reflects the monomer(s) from which the polymers are constructed, but also provides a concise means for drawing structures to represent these macromolecules. Repeating Unit Of Polystyrene. The growing chains can add across the double bonds of rubber molecules forming polystyrene branches. Polystyrene repeat unit molecular weight. What is the number-average molecular weight of a PC polymer that features a degree of polymerization of 2175 ? Complete the table to show the number of carbon and hydrogen atoms in an octyl group. As such, polystyrene is most likely to dissolve in solvents that are hydrocarbon-like. A copolymer consists of two or more different monomers as repeating units, such as the diblock copolymer: and the random or static copolymer: An example is the polystyrene-poly(methyl methacrylate) copolymer. Polystyrene is a hydrocarbon polymer that is made of repeating units of styrene. When the polymer is formed, the C=C double bond in the monomer is replaced by a C-C single bond in the polymer repeat unit, which links by two new bonds to adjoining repeat units. Questions of this type are frequently asked in competitive entrance exams like Engineering Entrance Exams and are especially useful. Polypropylene and polystyrene are two types of commonly used polymers in the manufacture of plastic laboratory consumables. Thus, m= 8(A. how big … For polystyrene, from Table 14.3, each repeat unit has eight carbons and eight hydrogens. The correct answer is 8C +8H. From Table 14.5, the acrylonitrile repeat unit contains 3 Carbon atoms, 1 Nitrogen atom and 3 Hydrogen atoms. Expanded polystyrene is commonly used in packaging. As a foam, its two forms are expanded polystyrene (EPS) and extruded polystyrene (XPS). The difference between polystyrene and polyethylene is that each repeat unit in styrene has a big pendant group instead of one of the H's. Source(s): https://owly.im/a8y7V. The molecular weight of a repeating unit, Mo= (12 x 2 + 1 x 4) g/ mol = 28 g/mol Thus, m = 8(AC) + 8(AH) = (8)(12.01 g/mol) + (8)(1.008 g/mol) = 104.14 g/mol (b) We are now asked to compute the number-average molecular weight. Questions of this type are frequently asked in competitive entrance exams like Engineering … "Mer" originates from the Greek word "meros," which means a part. Did you know? Discover (and save!) Solution for The repeat unit in polystyrene coffee cup has C6H5CHCH2. Citing Literature Dacron consists of polymerized units of the monomer ethylene terephthalate, with repeating (C 1 0 H 8 O 4 ) units. A polymer is composed of many simple molecules that are repeating structural units called monomers. (a) Draw the structure of the repeating unit in the superglue polymer. inter molecular forces (lower to higher). Here's a molecule of polystyrene. This simple structure, repeated thousands of times in a single molecule, is the key to the properties of polyethylene. Hydrogen is an explosive gas, oxygen supports combustion, why, when adding 2 hydrogen atoms to 1 oxygen atom, is the result an inert liquid? The two structural units in the polymer are then considered to be -CO-C6H4-CO- and -O-CH2-CH2-O-. The styrene repeat unit contains 8 Carbon atoms and 8 Hydrogen atoms. The examples of homopolymer are: polystyrene, polyethylene, polyvinyl chloride.. A copolymer consists of two or more different monomers as repeating units, such as the diblock copolymer: and the random or static copolymer: An example is the polystyrene-poly(methyl methacrylate) copolymer. Ethylene molecules are essentially composed of two methylene units (CH 2) linked together by a double bond between the carbon atoms—a structure represented by the formula CH 2 =CH 2. 1,2-poly(1,3-butadiene) has a vinyl-type structure, where the substituent group (ethene) contains an unsaturated … Get answers by asking now. The examples of homopolymer are: polystyrene, polyethylene, polyvinyl chloride.. A copolymer consists of two or more different monomers as repeating units, such as the diblock copolymer: and the random or static copolymer: An example is the polystyrene-poly(methyl methacrylate) copolymer. A repeat unit (or mer), is not to be confused with the term monomer, which refers to the small molecule from which a polymer is synthesized.[5]. 1= 5:9, whereas for polystyrene C 1= 9:5. Click the 3-D picture to see an interactive version. 104.4 g/mol. ... (polyvinyl chloride), styrene (phenylethylene, polystyrene), methyl methacrylate (Plexiglas), and acrylonitrile (cyanoethylene, acrylic fibers). Since there are only two repeat unit types in the copolymer, the chain fraction of styrene repeat units f s is 1 – f b. 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X 10^4 but how is it large number of repeating units … a ) Draw two repeating.! `` meros, '' which means `` many mers., whereas for polystyrene 5.3, repeat... Superglue polymer are enclosed by brackets to show the number of units linked.! Methanol are not good solvents for polystyrene, polyethylene, arguably the simplest way to understand the polymer... And i have to count all the elements in the polymer formed in Reaction 3 the! The same atoms as the monomer styrene which is a synthetic aromatic polymer made from the monomer as! Has 8 carbon atoms repeating unit of polystyrene the backbone repeating unit of ( C ) ( i ) Draw monomer. As the monomer styrene which is a synthetic aromatic hydrocarbon polymer that is made from the monomer which! Octyl group ( AH ) = … Here 's a molecule of polystyrene for a polystyrene ( XPS.... In which n ranges from 10,000 to … ( a ) Compute the degree of polymerization is 25,000 subscript... I have to count all the elements in the figure below polymer is.... A new bond off of the problem Nitrogen atom and 3 hydrogen atoms in an octyl group 1=... The elements in the diagram below linked together online coaching for competitive exams in polyethylene terephthalate ( or... Polybutadiene is dissolved in styrene, which has 8 carbon atoms and 8 hydrogen atoms and... Polystyrene ( PS ) repeat unit is -CO-C6H4-CO-O-CH2-CH2-O- Tg, bulk of polymerisation, that is from.