摘要:
The present invention relates to a photopolymerizable composition, which comprises: (a) a block copolymer component comprising an unhydrogenated styrene diene block copolymer and a hydrogenated controlled distribution styrene diene block copolymer (b) one or more photopolymerizable ethylenically unsaturated low molecular weight compounds, (c) one or more polymerization initiators, and optionally (d) from 0 to 40% by weight, based on the total photopolymerizable compositions, of one or more auxiliaries. The invention also includes flexographic printing plates derived from said photopolymerizable compositions, and flexographic printing relief forms prepared from said plates.
摘要:
The present invention relates to articles prepared from novel anionic block copolymers of mono alkenyl arenes and conjugated dienes, and to blends of such block copolymers with other polymers. The block copolymers are selectively hydrogenated and have mono alkenyl arene end blocks and conjugated diene mid blocks. The block copolymer may be blended with at least one other polymer selected from the group consisting of olefin polymers, styrene polymers, amorphous resins and engineering thermoplastic resins.
摘要:
The present invention is an improvement upon the known method of anionically polymerizing monomers by contacting the monomers with an anionic polymerization initiator which is an organo-substituted alkali metal compound. The improvement comprises decreasing the viscosity of the polymer cement by adding at least 0.01 equivalent of a metal alkyl compound per equivalent of alkali metal initiator if the metal alkyl is added before or at the beginning of polymerization. If the metal alkyl is added during the polymerization or after but before the living polymer is terminated, then at least 0.01 equivalent of the metal alkyl compound per equivalent of living polymer chain ends is should be used. The alkyl groups of the metal alkyl are chosen such that they do not exchange with the organo substituents of the alkali metal, which can be the living polymer chain ends or the organo substituents of the initiator. To avoid this undesired exchange reaction, the alkyl groups of the metal alkyl compound are selected to be more basic and/or less bulky or both than the organo substituents of the alkali metal compound.
摘要:
This invention is an improvement upon the current process for the production of block copolymers, especially hydrogenated block copolymers, of conjugated dienes and/or vinyl aromatic hydrocarbons which comprises anionically polymerizing the monomers in an inert hydrocarbon solvent in the presence of an alkali metal initiator whereby a polymer cement is produced and then contacting the cement with hydrogen under hydrogenation conditions in the presence of a hydrogenation catalyst. This invention and the improvement to the foregoing process comprises reducing the viscosity of the polymer cement by adding to it, preferably prior to hydrogenation (if the polymer is to be hydrogenated), from 2 to 50 % wt of a polar compound. The polar compound must be a poorer solvent for the block copolymer than is the inert hydrocarbon solvent. Preferred polar compounds include diethyl ether, tetrahydrofuran, diethoxyethane, monoglyme, diglyme, diethoxypropane, dioxane ortho-dimethoxybenzene, and the like.
摘要:
A pre-cursor block copolymer for sulfonation which, prior to hydrogenation, has the general configuration A-B-A, A-B-A-B-A, (A-B-A)nX, (A-B)nX, A-D-B-D-A, A-B-D-B-A, (A-D-B)nX, (A-B-D)nX or mixtures thereof, wherein A, B and D blocks do not contain any significant levels of olefinic unsaturation. Each A and D block is a polymer block resistant to sulfonation, and each B block is a polymer block susceptible to sulfonation. Each A block is a segment of one or more polymerized para-substituted styrene monomers, each B block contains segments of one or more vinyl aromatic monomers selected from polymerized (i) unsubstituted styrene monomers, (ii) ortho-substituted styrene monomers, (iii) meta-substituted styrene monomers, (iv) alpha-methylstyrene, (v) 1,1-diphenylethylene, (vi) 1,2-diphenylethylene and (vii) mixtures thereof, and each D block contains polymers having a glass transition temperature less than 20° C. and a number average molecular weight of between 1,000 and 50,000.
摘要:
A sulfonated block copolymer which is solid and non-dispersible in water having at least two polymer end blocks A and at least one polymer interior block B wherein each A block is a polymer containing essentially no sulfonic acid or sulfonate functional groups and each B block is a polymer block containing 10 to 100 mol percent sulfonic acid or sulfonate functional groups based on the number of monomer units of the B block, and wherein said A and B blocks do not contain any significant levels of olefinic unsaturation. Also claimed are processes for making such block copolymers, and the various end uses and applications for such block copolymers.
摘要:
The present invention is a, solid block copolymer comprising at least two polymer end blocks A and at least one polymer interior block B wherein each A block is a polymer block resistant to sulfonation and each B block is a polymer block susceptible to sulfonation, and wherein said A and B blocks do not contain any significant levels of olefinic unsaturation. Preferably, each A block comprising one or more segments selected from polymerized (i) para-substituted styrene monomers, (ii) ethylene, (iii) alpha olefins of 3 to 18 carbon atoms; (iv) hydrogenated 1,3-cyclodiene monomers, (v) hydrogenated monomers of conjugated dienes having a vinyl content less than 35 mol percent prior to hydrogenation, (vi) acrylic esters, (vii) methacrylic esters, and (viii) mixtures thereof; and each B block comprising segments of one or more polymerized vinyl aromatic monomers selected from (i) unsubstituted styrene monomers, (ii) ortho-substituted styrene monomers, (iii) meta-substituted styrene monomers, (iv) alpha-methylstyrene, (v) 1,1-diphenylethylene, (vi) 1,2-diphenylethylene and (vii) mixtures thereof. Also claimed are processes for making such block copolymers, and the various end uses and applications for such block copolymers.
摘要:
The present invention relates to articles prepared from novel anionic block copolymers of mono alkenyl arenes and conjugated dienes, and to blends of such block copolymers with other polymers. The block copolymers are selectively hydrogenated and have mono alkenyl arene end blocks and controlled distribution blocks of mono alkenyl arenes and conjugated dienes. The block copolymer may be blended with at least one other polymer selected from the group consisting of olefin polymers, styrene polymers, amorphous resins and engineering thermoplastic resins.
摘要:
The present invention relates to gels prepared from novel anionic block copolymers of mono alkenyl arenas and conjugated dienes, and to blends of such block copolymers with such polymers. The block copolymers are selectively hydrogenated and have A polymer blocks and B polymer blocks wherein A represents a polymer block of a mono alkenyl arene and B represents a polymer block of a conjugated diene. The block copolymer may be combined with tackifying resins, oils and other components to form the gel of the present invention.
摘要:
Cast polyurethanes are preferably formed from a hydrogenated polydiene diol having from up to 2 terminal hydroxyl groups per molecule and a number average molecular weight between 1000 and 20,000, an isocyanate having two or more isocyanate groups per molecule. This composition is then reacted with an amine curing agent at 80 to 130.degree. C. to form a cast elastomer with excellent hydrolytic stability. The amine curing agent must be a hindered aromatic amine crosslinker with low polarity and a solubility parameter of less than 10.5.