摘要:
Polymers comprising reversible hydrophobic functionalities are disclosed. The preferred embodiment polymers comprise Lewis acid segments and Lewis base segments. The polymer segments are, by themselves, hydrophilic and will either swell or dissolve in water. When the segments are incorporated into a polymer according to the present invention, the segments form water-insoluble or hydrophobic complexes. Upon changes in pH, temperature or solvent type, these complexes may dissociate, giving large transitions in polymer viscosity, emulsification ability, mechanical strength or transport properties. These polymers are useful as reversible emulsifiers which form stable emulsions at acidic pH and unstable emulsions at basic pH, as water-borne thickeners having low viscosity at low pH and high viscosity at high pH, as superabsorbing resins, or as coatings for pharmaceutical or agricultural agents.
摘要:
Polymers comprising reversible hydrophobic functionalities are disclosed. The preferred embodiment polymers comprise Lewis acid segments and Lewis base segments. The polymer segments are, by themselves, hydrophilic and will either swell or dissolve in water. When the segments are incorporated into a polymer according to the present invention, the segments form water-insoluble or hydrophobic complexes. Upon changes in pH, temperature or solvent type, these complexes may dissociate, giving large transitions in polymer viscosity, emulsification ability, mechanical strength or transport properties. These polymers are useful as reversible emulsifiers which form stable emulsions at acidic pH and unstable emulsions at basic pH, as water-borne thickeners having low viscosity at low pH and high viscosity at high pH, as superabsorbing resins, or as coatings for pharmaceutical or agricultural agents.
摘要:
A method to evaluate, determine and optimize production parameters for a coating application of a UV cationic polymerizable coating system to a substrate is provided. The method is based on a simulation model which includes both shadow and dark cure processes. Both of an active center generation process and the active center diffusion process are mathematically described. In the model, the two processes are considered separately since they are driven by different fundamental phenomena and occur on different timescales. Evaluation or prediction of the effect of process variables on the curing of a cationic coating of a complex substrate according to the described method allows characterization and understanding of process variables which may save set-up costs and improve production efficiency.
摘要:
An object of complex three-dimensional configuration, such as an automotive vehicle body, is coated with a combination of a coating formulation and a photoactivated mixture containing active centers that have been produced prior to application. The two liquids can be intimately mixed prior to application to the object, or the coating formulation can be applied prior to the application of the photoactivated mixture. The coating formulation is cured by the active centers that have been produced prior to application.
摘要:
A novel method for producing thick composite parts based upon photopolymerizable compositions is disclosed. Also disclosed are novel methods for encapsulation of microelectronic devices based upon novel photopolymerizable compositions. The constituents of the photopolymerizable mixture comprise a monomer or monomers capable of polymerizing by free radical or cationic mechanisms, and a photoinitiator system which possesses an absorbance characteristic which is effectively reduced, or self-eliminating, upon initiation of the polymerization reaction. Parts having thicknesses up to 2 cm and thicker for varying end use applications are made by photopolymerizing such compositions. In addition, using such compositions composite parts can be made using a reinforcement material such as a glass fiber mat present in an amount by weight of from about 5 to about 70%.
摘要:
A novel method for producing thick composite parts based upon photopolymerizable compositions is disclosed. The constituents of the photopolymerizable mixture comprise a monomer or monomers capable of polymerizing by free radical or cationic mechanisms, and a photoinitiator system which possesses an absorbance characteristic which is effectively reduced, or self-eliminating, upon initiation of the polymerization reaction. Parts having thicknesses up to 2 cm and thicker for varying end use applications are made by photopolymerizing such compositions. In addition, using such compositions composite parts can be made using a reinforcement material such as a glass fiber mat present in an amount by weight of from about 5 to about 70%.
摘要:
A method to evaluate, determine and optimize production parameters for a coating application of a UV cationic polymerizable coating system to a substrate is provided. The method is based on a simulation model which includes both shadow and dark cure processes. Both of an active center generation process and the active center diffusion process are mathematically described. In the model, the two processes are considered separately since they are driven by different fundamental phenomena and occur on different timescales. Evaluation or prediction of the effect of process variables on the curing of a cationic coating of a complex substrate according to the described method allows characterization and understanding of process variables which may save set-up costs and improve production efficiency.
摘要:
The invention relates to a method for applying a photo-activated layered polymer coating to a substrate material in which one or more layers do not contain photoinitiator, or are not exposed to initiating light, but cure due to migration of cationic active centers. At least two separate monomer layers are applied to the substrate material. At least one of the monomer layers includes a photoinitiator capable of producing cationic active centers. The at least one layer including the photoinitiator is exposed to a source of UV radiation at a desired wavelength forming cationic active centers. The at least two separate monomer layers react in a polymerization reaction forming a cured layered material. The cationic active centers of the exposed monomer layer migrate to the unexposed layer such that both layers cure via the polymerization reaction.
摘要:
A method for forming gas or liquid aphrons with reversible surfactants or emulsifiers is described. Polymers which change their emulsifying properties upon change of pH, temperature or other condition are used to form the aphrons. The aphrons are useful for chemical reactions and separations, mass transfer processes, and for biological processes.
摘要翻译:描述了用可逆表面活性剂或乳化剂形成气体或液体香料的方法。 使用在pH,温度或其他条件改变时改变其乳化性能的聚合物形成香料。 ap s可用于化学反应和分离,传质过程和生物过程。
摘要:
A method and apparatus (10) for detection of the degree of cure of a polymer in situ and non-invasively. The method and apparatus uses a solvatochromic probe molecule which upon curing produces a shift in the fluorescence emission spectrum as compared to a liquid polymerizable composition. The method and apparatus is particularly adapted for poly(vinyl) polymers. Preferred solvatochromic probe molecules are oxazones and pyrene.