A composition includes: at least one polymer represented by formula (1), formula (2), or both; and a solvent. A.sup.1 and A.sup.2 are each independently a structural unit having 2 or more carbon atoms; a plurality of A's are the same or different and a plurality of A.sup.2s are the same or different; n1 and n2 are each independently an integer of 2 to 500; R.sup.1, R.sup.2, and R.sup.3 are each independently an organic group having 1 or more carbon atoms, or R.sup.1 and R.sup.2 taken together represent a ring together with X.sup.1, Y.sup.1, and P; R.sup.1 and R.sup.2 are the same or different; X.sup.1, Y.sup.1, and Y.sup.2 are each independently a single bond, —O—, or —NR.sup.4—; R.sup.4 is an organic group having 1 or more carbon atoms; and Z.sup.1 and Z.sup.2 are each independently hydrogen or an organic group having 1 to 15 carbon atoms.

##STR00001##

Provided are a terminally modified diene-based polymer having excellent mechanical properties and also a method for producing the same. The terminally modified diene-based polymer is obtainable by allowing a diene-based polymer terminated with ketone or aldehyde groups to react with an aminophosphonic acid compound represented by general formula (1) or (2): ##STR00001##
wherein in formulas (1) and (2), R.sub.1 and R.sub.4 each represent a C.sub.1-10 alkanediyl group, R.sub.2 and R.sub.3 may be the same or different and each represent hydrogen, a C.sub.1-3 alkyl group, or a phenyl group, R.sub.5, R.sub.6, R.sub.8, and R.sub.9 may be the same or different and each represent hydrogen, a C.sub.1-3 alkyl group, or a phenyl group, and R.sub.7 represents hydrogen or a hydroxyl group.

Provided are a terminally modified diene-based polymer having excellent mechanical properties and also a method for producing the same. The terminally modified diene-based polymer is obtainable by allowing a diene-based polymer terminated with ketone or aldehyde groups to react with an aminophosphonic acid compound represented by general formula (1) or (2): ##STR00001##
wherein in formulas (1) and (2), R.sub.1 and R.sub.4 each represent a C.sub.1-10 alkanediyl group, R.sub.2 and R.sub.3 may be the same or different and each represent hydrogen, a C.sub.1-3 alkyl group, or a phenyl group, R.sub.5, R.sub.6, R.sub.8, and R.sub.9 may be the same or different and each represent hydrogen, a C.sub.1-3 alkyl group, or a phenyl group, and R.sub.7 represents hydrogen or a hydroxyl group.

A method for preparing a modified conjugated diene-based polymer is provided. The method is characterized in adding a polyoxyethylene phosphate ester-based compound having a specific structure together with sulfur chloride modifier during modification, by which modification reproducibility may be markedly improved, stable process may be performed, the changing degree of the physical properties, specifically a Mooney viscosity increasing ratio and the degree of branching of a modified conjugated diene-based polymer according to modification conditions may be anticipated, and the changing degree of a Mooney viscosity increasing ratio and the degree of branching may be easily controlled by controlling modification conditions.

A modified conjugated diene-based polymer having high linearity and improved compounding properties is provided. The modified conjugated diene-based polymer includes phosphor, sulfur and chlorine in specific amount ranges, and the degree of branching is controlled, and accordingly, if applied to a rubber composition, tensile strength and viscoelasticity may be excellent, and processability may be markedly improved.

An object of the present disclosure is to provide a polymer which is recyclable and capable of performing as equally well as a new product. Another object of the present disclosure is to provide a rubber composition containing said polymer, a method for manufacturing said rubber composition, and a rubber product containing said rubber composition. To achieve the objects, the present disclosure provides a complex polymer, comprising: a polymer main chain containing a conjugated diene unit and/or an olefin unit; and a functional group bonded to the polymer main chain, wherein: the functional group contains nitrogen atom and/or phosphorus atom therein and is complexed with a metal ion of an element of group 7-10 in the Periodic Table; and the bond dissociation energy for dissociation of the metal ion and the functional group is 200 kJ/mol or more.

An object of the present disclosure is to provide a polymer which is recyclable and capable of performing as equally well as a new product. Another object of the present disclosure is to provide a rubber composition containing said polymer, a method for manufacturing said rubber composition, and a rubber product containing said rubber composition. To achieve the objects, the present disclosure provides a complex polymer, comprising: a polymer main chain containing a conjugated diene unit and/or an olefin unit; and a functional group bonded to the polymer main chain, wherein: the functional group contains nitrogen atom and/or phosphorus atom therein and is complexed with a metal ion of an element of group 7-10 in the Periodic Table; and the bond dissociation energy for dissociation of the metal ion and the functional group is 200 kJ/mol or more.

A method for preparing a modified conjugated diene-based polymer is provided. The method is characterized in adding a polyoxyethylene phosphate ester-based compound having a specific structure together with sulfur chloride modifier during modification, by which modification reproducibility may be markedly improved, stable process may be performed, the changing degree of the physical properties, specifically a Mooney viscosity increasing ratio and the degree of branching of a modified conjugated diene-based polymer according to modification conditions may be anticipated, and the changing degree of a Mooney viscosity increasing ratio and the degree of branching may be easily controlled by controlling modification conditions.

The present invention relates to a super absorbent polymer which not only has excellent basic absorption performance but also can improve rewet characteristics and leakage suppression characteristics of hygienic materials such as diapers, and a method for preparing the same. The super absorbent polymer includes: a base polymer powder including a first cross-linked polymer of a water-soluble ethylenically unsaturated monomer having an acidic group of which at least a part is neutralized; and a surface crosslinked layer that is formed on the base polymer powder and includes a second cross-linked polymer in which the first crosslinked polymer is further crosslinked via a surface crosslinking agent, wherein the surface crosslinking agent includes a mixture of plural kinds of cyclic alkylene carbonates, and where the mixture has a Hansen solubility parameter by hydrogen bonding component of 13 or more.

An end-modified diene polymer having excellent mechanical properties and a method for producing the polymer are provided. An end-modified diene polymer having at least one of the structures represented by the following formulae (1) to (4) at the end thereof:

##STR00001##

wherein Rs which may be the same or different each represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and m and l which may be the same or different, respectively, each represent an integer of 2 or more.