Ring opening metathesis

Suitable non-hydrogen substituents may be chosen from the substituents described hereinabove. Applications in Organic Synthesis R. The method of claim 1, wherein said reacting step comprises the steps of: Chain transfer can also be used to improve processability of the resulting polymer — addition of an acyclic olefin chain-transfer agent can limit chain molecular weights and introduce terminal functional groups.

Olefin metathesis

To address this question, copolymer samples were prepared with partially deuterated imidazole blocks, and adsorbed films of these copolymers were examined by neutron reflectivity. Monomers Monomer a FIG. Examples of such substituents include, without limitation: The active end can "backbite" the chain, forming a macrocycle.

As seen in FIG. To polymerize these moieties, one of the rings has to open prior polymerization. Control over these and other properties is possible for reactions using only a single cyclic olefin, but it will be appreciated that the use of a plurality of cyclic olefins further enhances the range of possible metathesis products.

The catalyst is typically added to the reaction medium as a solid, but may also be added as a solution wherein the catalyst is dissolved in an appropriate solvent, or as a suspension wherein the catalyst is suspended in an appropriate liquid. The hydrophobic carbon chain may be substituted or unsubstituted, may contain one or more heteroatoms such as N3 O, S or P, may contain one or more functional groups such as those described hereinabove, and may contain one or more unsaturated regions e.

It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting.

When the cyclic olefin comprises more than one ring, the rings may or may not be fused. If the monomer is bicyclic it will not undergo metathesis polymerization if the fluorine substituent is present in the same ring as the double bond.

A method for bonding solids to thermoset resins comprising: For example, two cyclic olefins selected from the cyclic olefins described hereinabove may be employed in order to form metathesis products that incorporate both cyclic olefins. This eliminates the possibility of failure between CA layers.

A further advantage of the present invention is that only a monolayer of the BC CA is present at the interface. In one embodiment, a method is provided for carrying out a catalytic ring-opening cross-metathesis reaction, comprising contacting at least one olefinic substrate with at least one cyclic olefin as a cross metathesis partner, in the presence of a ruthenium alkylidene olefin metathesis catalyst under conditions effective to allow ring insertion cross metathesis whereby the cyclic olefin is simultaneously opened and inserted into the olefinic substrate.

The hydrophobic portion is a carbon chain that typically contains at least six carbon atoms, and may contain up to 20 or more carbon atoms in the chain.

Common rings, 5- through 7-membered cycloalkenes, have a high tendency for formation and are often under greater thermodynamic control due to the enthalpic favorability of the cyclic products, as shown by Illuminati and Mandolini on the formation of lactone rings.

For example, the density of cross-linking points can be controlled in polymers and macromonomers prepared using the methods disclosed herein. Most monomers that undergo AROP contain polar bonds like ester, amide, carbonate, urethane, epoxide, and phosphate which polymerize to the corresponding polyester, polyamide, polycarbonate, polyurethane, polyepoxide, and polyphosphate.

Adhesion testing Lap shear coupons were machined from copper blocks. Each fatty acid- derived fragment of the olefinic substrate may independently be saturated, monounsaturated, or polyunsaturated,- and may furthermore derive or be derivable from naturally-occurring fatty acids or from synthetic fatty acids.

Typical cyclic monomers that can be polymerized via ROP are di-functional monomers that carry two different reactive groups like one amine or alcohol and one carboxylic acid that have undergone a cyclization reaction. Following the adsorption step, the samples were thoroughly washed with MeOH and THF to remove any copolymer not strongly adsorbed to the surface.

Ring-opening Metathesis Polymerization

Careful balance of catalyst, monomer, and other factors can offer excellent control of the polymer structure. Sample set 3 was composed of coupons which were microetched, Ring opening metathesis, left in air for 3 h to allow the native oxide to form, immersed in a 0.

Q is a linker, typically a hydrocarbylene linker, including substituted hydrocarbylene, heteroatom-containing hydrocarbylene, and substituted heteroatom-containing hydrocarbylene linkers, wherein two or more substituents on adjacent atoms within Q may also be linked to form an additional cyclic structure, which may be similarly substituted to provide a fused polycyclic structure of two to about five cyclic groups.

Some examples of cyclic monomers that polymerize through anionic or cationic ring-opening polymerization include cyclic ethers, lactones, lactams, and epoxides.

The active centers of AROP monomers are nucleophilic and also act as bases to abstract protons from the monomer, initiating new chains. There is no kinetic data available to allow comparison of the polymerization of unsubstituted cycloalkenes.

Free radical ring-opening polymerization is often utilized to copolymerize ring-opening monomers with various kinds of vinyl monomers and other heterocyclic monomers. In a three-neck, ml round-bottom flask was placed 4. The method of claim 2 wherein the solid is an inorganic material other than a metal.

Unless otherwise specified, the components of a kit of parts may be packaged individually. A "lower alkoxy" group intends an alkoxy group containing 1 to 6 carbon atoms.

Sample set 1 was composed of FR4 epoxy roll-coated directly onto the native oxide of coupons which had been microetched and rinsed.Summary; Ring-opening Polymerization.

is another form of chain-growth polymerization, in which the terminal end group of a polymer chain acts as a reactive center where further cyclic monomers can react by ring-opening and additon of the broken bond to form a longer polymer chain.

Ring-opening metathesis polymerization (ROMP) is a chain growth polymerization process where a mixture of cyclic olefins is converted to a polymeric material (see Fig.

1 for an illustrative example).The mechanism of the polymerization is based on olefin metathesis, a unique metal-mediated carbon–carbon double bond exchange process.

Ring Opening Metathesis (Polymerization) - ROM(P) Strained rings may be opened by a ruthenium carbene-catalyzed reaction with a second alkene following the mechanism of the Cross Metathesis.

The driving force is the relief of ring strain. In addition to the metathesis of strained cyclic and exocyclic olefins, the remarkable functional group tolerance (alcohols, aldehydes, carboxylic acids) and stability toward air, water.

Ring-opening metathesis polymerization One polymerization strategy that meets many of the requirements listed above is based on the ring-opening metathesis polymerization of strained cyclic olefins (such as DCPD). SynonymsRing-opening olefin metathesis polymerizationDefinitionRing-opening metathesis polymerization (ROMP) is a form of chain-growth polymerization based on the olefin metathesis .

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Ring opening metathesis
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