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Topic: Addition polymer

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In the News (Sat 20 Jul 19)

  Chemical of the Week -- Polymers
Polymers are substances whose molecules have high molar masses and are composed of a large number of repeating units.
Polymers are formed by chemical reactions in which a large number of molecules called monomers are joined sequentially, forming a chain.
Polymers are classified by the characteristics of the reactions by which they are formed.
scifun.chem.wisc.edu /chemweek/POLYMERS/Polymers.html   (1917 words)

  POLYMER. The Columbia Encyclopedia: Sixth Edition. 2000   (Site not responding. Last check: )
An addition polymer is one in which the molecular formula of the repeating structural unit is identical to that of the monomer, e.g., polyethylene and polystyrene.
A condensation polymer is one in which the repeating structural unit contains fewer atoms than that of the monomer or monomers because of the splitting off of water or some other substance, e.g., polyesters and polycarbonates (see illustration).
Polymerization, the chemical process of forming polymers from their component monomers, is often a complex process that may be initiated or sustained by heat, pressure, or the presence of one or more catalysts.
www.bartleby.com /aol/65/po/polymer.html   (335 words)

 Addition polymer - Wikipedia, the free encyclopedia
An addition polymer is a polymer which is formed by an addition reaction, where many monomers bond together via rearrangement of bonds without the loss of any atom or molecule.
This is in contrast to a condensation polymer which is formed by a condensation reaction where a molecule, usually water, is lost during the formation.
With the exception of combustion, the backbone of addition polymers are generally chemically inert.
en.wikipedia.org /wiki/Addition_polymer   (418 words)

 terms.html   (Site not responding. Last check: )
Polymers that can be repeatedly melted and solidified (without damage) are said to be thermoplasts; those that solidify once but will not melt again with damage are said to be thermosets.
Polymers of all types in which the long chains are produced by joining two or more different kinds of monomers are termed copolymers.
Addition polymers are those in which the monomers join at unsaturated carbon atoms; several are summarized in theTable.
www.owlnet.rice.edu /~chem122/Lab122/polymers/therms.html   (1078 words)

 Anionic polymer products and processes - Patent 6221956
Aqueous dispersions of water-soluble polymers are preferably formed by polymerization of the corresponding monomers in an aqueous inorganic salt solution to form the first anionic water-soluble polymer, preferably in the presence of at least one second anionic water-soluble polymer.
Polymer dosages are generally chosen to be effective to flocculate the solids and may be found by routine experimentation in a manner known to those skilled in the art.
Additional ammonium sulfate was added during the polymerization to lower the bulk viscosity while increasing the salt concentration to the appropriate level.
www.freepatentsonline.com /6221956.html   (12876 words)

 Biodegradable Polymers
Addition polymers form when a radical initiator adds to a carbon-carbon double bond to yield a reactive intermediate.
Polymer manufacturers are willing to accept break down of a polymer structure into smaller fragments that still contain the polymer.
The reason starch is added to the polymers is that some microorganisms utilize starch, a polymer of glucose, as a nutrient source and secrete enzymes to break it down for consumption.
www.denison.edu /chem/DCS/journal/_scottv1n1.html   (1758 words)

 Definitions of Terms
The decision to classify a polymer as branched or cross-linked is based on the extent to which the side-chains on the polymer backbone link adjacent polymer chains.
Cross-linked polymers are insoluble in all solvents because the polymer chains are tied together by strong covalent bonds.
Addition polymers can be recognized by noting that the repeating unit always has the same formula as the monomer from which the polymer is formed.
chemed.chem.purdue.edu /genchem/topicreview/bp/1polymer/terms.html   (1369 words)

 Macromolecules: Natural and Synthetic Polymers   (Site not responding. Last check: )
Polymers are substances composed of extremely large molecules termed macromolecules, with molecular masses ranging from 104 to 108 amu.
The molar mass of the polymer is quoted as an average molar mass.
Both natural and synthetic polymers are ubiquitous in our lives: elastomers (polymers with elastic, rubber-like properties), plastics (the first plastic was used in 1843 to make buttons), textile fibers, resins, and adhesives.
www.owlnet.rice.edu /~chem122/lab/polymers   (2690 words)

 [No title]
Of the two basic types of polymer (addition and condensation) the addition polymer is the simpler in that it is formed by direct addition of monomer units to the end of a growing polymer chain.
With respect to flammability, the yield of volatiles from the thermal decomposition of a polymer is much less for highly cross-linked structures since much of the material forms an involatile carbonaceous char, thus effectively reducing the potential supply of gaseous fuel to a flame.
A natural polymer that exhibits a high degree of cross-linking is lignin, the 'cement' that binds the cellulose structures together in higher plants, thus imparting greater strength and rigidity to the cell walls.
www.fire-hyondai.co.kr /02-02.doc   (3142 words)

 Polymerization Reactions
It isn't difficult to form addition polymers from monomers containing C=C double bonds; many of these compounds polymerize spontaneously unless polymerization is actively inhibited.
Addition polymers can also be made by chain reactions that proceed through intermediates that carry either a negative or positive charge.
Free-radical polymerization of ethylene produces a low-density, branched polymer with side chains of one to five carbon atoms on up to 3% of the atoms along the polymer chain.
chemed.chem.purdue.edu /genchem/topicreview/bp/1polymer/reactions.html   (991 words)

 specialchem, polymer additive, plastics additives, polymer compounds
A recent addition to the number of Internet portal websites for the plastics industry is SpecialChem (www.specialchem.com).
The website is designed to help users of plastics additives source the right additive for a particular application.The site provides free access to all the sources of information required to make the choice, such as data sheets and technical reports, as well as providing contact details for the manufacturers of additives.
In addition, features, benefits and qualitative properties of the additive, such as non-staining or low volatility, can be used.
www.specialchem4polymers.com /specialchem.htm   (280 words)

 Of Fluorinated Addition Polymer From Unsaturated Monomers - Addition Polymer Is Perhalogenated patents
Of Fluorinated Addition Polymer From Unsaturated Monomers - Addition Polymer Is Perhalogenated patents
Addition Polymer Is Perhalogenated patent applications listed are from June 2005 to current and include Date, Patent Application Number, Patent Title, Patent Abstract summary and are linked to the corresponding patent application page.
The invention relates to use of a tetrafluoroethylene/perfluoroolefin copolymer applied as a primer powder in conjunction with a powder overcoat of tetrafluoroethylene/perfluoro (vinyl alkyl ether) copolymer, also known as perfluoroalkoxy polymer (PFA), which when baked onto a substrate gives superior and more durable adhesion of the coating system to the...
www.freshpatents.com /x1428422000psbc.php   (641 words)

 addition polymers - HighBeam Encyclopedia   (Site not responding. Last check: )
Improvement of the processability of poly(ether ketone ketone) by the addition of a thermotropic liquid crystalline polymer.
Eastar Copolyester EB062 is newest addition to The Glass Polymer portfolio for cosmetic, personal care packaging; Offers a thick-walled alternative to glass, provides outstanding clarity, toughness and design flexibility.
Reinforcement of mechanical properties of a poly(ethylene terephthalate) and polycarbonate blend by the addition of thermotropic liquid crystalline polymer.
www.encyclopedia.com /doc/1E1-x-additpoly.html   (291 words)

 Additional suggested operating instructions for manufacturing Elvaloy® RET modified asphalt, using catalyst ...
After polymer is mixed in, startup polymer addition at a rate of 5 lb/min less than previous rate.
If no polymer buildup is encountered at 30 lb/min for one hour, increase polymer addition rate by 10 lb/min, wait one hour, if no polymer buildup, increase rate by another 10 lb/min.
Polymer is added to the asphalt as it is being pumped from the base asphalt tank to the product tank in a continuous mode of operation.
www.dupont.com /asphalt/H-81614.html   (2561 words)

 Suggested operating instructions for the manufacture of polymer modified asphalt using Elvaloy® RET
After polymer is mixed in, restart polymer addition at a rate of 5 lb/min less than previous rate.
After the optimum polymer addition rate is determined, check this rate over the next few production runs to ensure there is no buildup on top of the tank.
Polymer addition rate is 30 lb/min (1,800 lb/hr), asphalt is transferred between the two tanks at 90,000 lb/hr (Addition rate verified in previous tests with this asphalt, and is equal to the polymer addition rate divided by the percentage of polymer in the final product.)
www.dupont.com /asphalt/H-81613.html   (1784 words)

Efficient retention of the polymers onto the fibers, even up to a level of equal amounts of polymer and fiber, was evident from the basis weight of handsheets prepared from a constant amount of fiber.
Practical upper limits of polymer addition for the dual-polymer system were evident from an increasing stickiness of undried paper handsheets, with increasing polymer dosage.
Sequential addition of poly-diallyldimethylammonium chloride, which is highly cationic, followed by anionic carboxymethylcellulose, has been found to promote inter-fiber bonding during the manufacture of paper, with potential benefits to the recycling of fibers.
www4.ncsu.edu /~hubbe/abstracts.htm   (12361 words)

 Chem 381- CHAPTER TWO- part 1
monomer is soluble and the polymer is soluble in the diluent:
monomer is soluble and the polymer is insoluble in the diluent:
The properties of the polymer are similar to those of the same polymer made by a bulk polymerization.
web.umr.edu /~wlf/CHEM381/chap21.html   (2448 words)

 CYN Polymer Revolution
The addition reactions of alkenes with the following: bromine, hydrogen bromide, hydrogen in the presence of a catalyst, and water in the presence of a catalyst.
The mechanism of the electrophilic addition reaction between bromine and an alkene.
The relationship between the properyies of addition polymers and aspects of their molecular structure: chain length, side-groups, chain branching, chain flexibility, cross-linking and stereoregularity.
www.york.ac.uk /org/seg/salters/chemistry/checknotes/CheckN7.html   (338 words)

 Addition Polymers   (Site not responding. Last check: )
Unlike condensation (step-growth) polymers, which release small molecules, like water, as they form, the reactions that lead to addition, or chain-growth, polymers incorporate all of the reactants’ atoms into the final product.
Addition polymers are usually made from molecules that have the following general structure:
If one of the four atoms connected to the carbons in the monomer’s double bond is chlorine and the others are hydrogen, the monomer is vinyl chloride, and the polymer it forms is poly(vinyl chloride) or PVC.
www.mpcfaculty.net /mark_bishop/addition_polymers.htm   (431 words)

 [No title]
Polymer — a molecule with a large molecular mass; a chain formed of repeating small units.
Addition polymerization is when building blocks or monomers add to one another in such a way that the polymeric product contains all the atoms of the starting monitors.
Condensation Polymerization is a portion of monomer molecule that is no incorporated in the final polymer but is split out as the polymer is formed.
academics.vmi.edu /chem_jt/ch132/6-4chemhw10.doc   (634 words)

 Condensation polymer - Wikipedia, the free encyclopedia
Condensation polymers are any class of polymers formed through a condensation reaction, releasing (or condensing) a small molecule by-product such as water or methanol, as opposed to addition polymers which involve the reaction of unsaturated monomers.
This method, however, is expensive and ineffective, so the addition polymer of ethene (polyethylene) is generally used.
The most commonly known condensation polymers are proteins, fabrics such as nylon, silk, or polyester.
en.wikipedia.org /wiki/Condensation_polymer   (410 words)

 polymer — FactMonster.com
An addition polymer is one in which the molecular formula of the repeating structural unit is identical to that of the monomer, e.g., polyethylene and
A condensation polymer is one in which the repeating structural unit contains fewer atoms than that of the monomer or monomers because of the splitting off of water or some other substance, e.g., polyesters and
polyolefins - polyolefins, group of plastics that are polymers of various alkenes, or olefins.
www.factmonster.com /ce6/sci/A0839593.html   (363 words)

 Egypt mint considers a switch to plastic
In addition, polymer notes last five times as long as paper notes.
In addition, polymer banknotes are more environmentally friendly.
Paper notes have to be burnt after a while, while polymer banknotes are recyclable.
www.polymernotes.org /articles/EGY_article_switch.htm   (364 words)

Single repeating unit of a large molecule or polymer is called a “monomer”;.
The empirical formula of addition polymer and the monomer is same.
Condensation polymers are formed by the combination of monomers with the elimination of simple molecules such as H
www.citycollegiate.com /organic1.htm   (326 words)

 addition polymers — Infoplease.com
polymer - polymer, chemical compound with high molecular weight consisting of a number of structural units...
Reinforcement of mechanical properties of a poly(ethylene terephthalate) and polycarbonate blend by the addition of thermotropic liquid......
Polymers for water-based coatings - a systematic overview.
www.infoplease.com /ce6/sci/A0909927.html   (166 words)

 Demonstration 1:Polymers
Objective: The objective of this demonstration is to produce an addition polymer using a free radical initiator.
Because the high rate and heat of polymerization of acrylates make control of bulk polymerization impractical, the most important method of preparation is by emulsion polymerization.
The polymer is coagulated in a concentrated solution of sodium chloride to yield a white product.
matse1.mse.uiuc.edu /~tw/polymers/a.html   (617 words)

 Chapter 23 Notes
addition polymer - a polymer that consists of a repeat unit equivalent to its monomer - generally vinyl polymers, e.g., polyethylene, or ring-opening polymers, e.g., poly(ethylene oxide)
polymer structure has substituents on alternate carbons because each addition is preferred in the same direction
However, chiral centers in most vinyl polymers are asymmetric only by virtue of the differing chain lengths and end groups in either direction.
chem.pdx.edu /~wamserc/C336S99/23notes.htm   (1953 words)

 Putting Them Together
You might say that an addition polymer is like a good friend who accepts everything about you, the pleasant and the unpleasant alike.
But a condensation polymer is more like a snotty social club that says, "Sure you can join, but only if you ditch those friends of yours".
Because there is less mass in the polymer than in the original monomers, we say that the polymer is condensed with regard to the monomers.
www.pslc.ws /macrog/synth.htm   (987 words)

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