Polyether synthesis: From activated or metal-free anionic ring-opening polymerization of epoxides to functionalization

Activation in anionic polymerization: Why phosphazene bases are very exciting promoters

A semiconductor device production system using a laser crystallization method is provided which can avoid forming grain boundaries in a channel formation region of a TFT, thereby preventing grain boundaries from lowering the mobility of the TFT greatly, from lowering ON current, and from increasing OFF current. Rectangular or stripe pattern depression and projection portions are formed on an insulating film. A semiconductor film is formed on the insulating film. The semiconductor film is irradiated with continuous wave laser light by running the laser light along the stripe pattern depression and projection portions of the insulating film or along the major or minor axis direction of the rectangle. Although continuous wave laser light is most preferred among laser light, it is also possible to use pulse oscillation laser light in irradiating the semiconductor film.

Semiconductor device and semiconductor device production system

An aliphatic polyester improved provided by using water positively as an initiator or/and a molecular weight-adjusting agent, is improved in moisture resistance. More specifically, a cyclic ester containing proton-source compounds including more than 80 ppm of water as an initiator or/and a molecular weight-adjusting agent, is subjected to ring-opening polymerization, and the resultant aliphatic polyester is compounded with a carboxyl group-capping agent to produce such an aliphatic polyester.

Process for producing aliphatic polyester

The present invention provides a sealant composition that includes a reactive silyl group-containing organic polymer, and gives a cured product having a low modulus and not having wrinkles or cracks on the surface even though the sealant includes as a curing catalyst a tetravalent tin compound, which is presumed to reduce recovery. The sealant composition is a one-component curable sealant composition including: a linear organic polymer (A) having a number average molecular weight of 11,000 to 30,000, and having an ethanol-elimination reactive silyl group at a molecular terminal; a tetravalent tin compound (B); and a plasticizer (C).

Curable composition and cured product thereof

PROBLEM TO BE SOLVED: To obtain a polyalkylene oxide having no residual odor without using any special metal component by polymerizing an alkylene oxide compound in the presence of a polyphosphazene cation salt and an active hydrogen compound, or a salt of the cation and an active hydrogen compound anion. SOLUTION: The polyphosphazene cation is shown in formula I (wherein a is 7 to 200; R is a 1-7C hydrocarbon group, and two R's on the same nitrogen atom may be combined to form a ring structure; and Z is an alkoxy anion, an aryloxy anion, a carboxy anion, or a hydroxy anion), or formula II (wherein a and R are as defined in formula I; and Q is an anion comprising an active hydrogen compound having one proton released therefrom). The active hydrogen compound used comprises water, preferably methanol or ethanol. The salt represented by formula I is used in an amount of 1×10 to 1 mol per mol of the active hydrogen compound. An example of the alkylene oxide compound used is ethylene oxide.

Production of polyalkylene oxide

Poly(alkylene oxide) which does not contain any metallic component and does not
leave an odor is prepared simply and efficiently, by a process using a polymerization
initiator which does not cause any problems in preparing and handling in the preparation
of the polyalkylene oxide by polymerizing an alkylene oxide compound, and does not
require special treatment before the initiation of the polymerization. In the process, the
alkylene oxide compound is polymerized in the presence of a phosphine oxide compound
represented by the formula (1):
 
wherein Rs are the same or different and each represents a hydrocarbon group having 1
to 10 carbon atoms, and x represents an amount of water molecules contained in terms
of a molar ratio and is within a range from 0 to 5.0. If desired, the alkylene oxide compound can be polymerized in the presence of said
phosphine oxide compound and an active hydrogen compound selected from water or an 
organic compound having a partial structural formula -OH or
-NH-.

Process for preparing poly(alkylene oxide)

PROBLEM TO BE SOLVED: To obtain a new compound being a basic compound soluble in an organic solvent, having a high catalytic action in a reaction between an epoxy compound and an acid anhydride. SOLUTION: This compound is shown by formula I (Q is pyrrolidino or piperidino) such as tris(tripyrrolidinophosphoranylideneamino)phosphine oxide. The compound of formula I is obtained by reacting (A) phosphorus oxychloride with (B) a compound of formula II (e.g. iminotripyrrolidinophosphorane, etc.), by using preferably 6-8 mols of the component B based on 1 mol of the component A generally in a solvent such as o-dichlorobenzene, etc., preferably at 0-200 deg.C for 2-30 hours.

Phosphine oxide compound and its production

This contribution reports development and an application of high-performance catalysts, phosphazene catalysts (PZN and PZO) with high reactivity and selectivity for ring-opening polymerization reactions of propylene oxides that provide highly advanced polypropylene glycols. The produced polypropylene glycols with high purity and narrow molecular weight distributions have been commercialized as raw materials for environmentally- and people-friendly polyurethane foams (for car sheet cushions).

Development of Novel Molecular Catalysts Phosphazene Catalysts for Commercial Production of Highly Advanced Polypropylene Glycols

A process of preparing a polymer comprises conducting ring-opening polymerization of a 4- to 10-membered ring-opening polymerizable cyclic monomer in the presence of a phosphazenium salt of an active hydrogen compound represented by the chemical formula (1) : wherein n is an integer of 1 to 8 and indicates the number of phosphazenium cations, Zn- is an anion of a n-valent active hydrogen compound derived by releasing n protons from an active hydrogen compound having a maximum of 8 active hydrogen atoms, a, b, c and d are individually a positive integer or 0 and are not all 0 at the same time, R's are the same or different hydrocarbons having 1 to 10 carbon atoms, and two R's located on each common nitrogen atom may be coupled together to form a ring structure ; or in the presence of the phosphazenium salt of the active hydrogen compound and the active hydrogen compound. The process can produce a polymer by ring-opening polymerization of a 4- to 10-membered ring-opening polymerizable cyclic monomer in the presence of an initiator which causes no specific problems in terms of preparation and handling, contains no metallic ingredients and has no residual odor.

Process of preparation of a polymer in the presence of a phosphazenium salt

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