TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Composition: The salt includes lithium salt.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Composition: The vinyl aromatic monomer has structure of formula: R10R11C=CR12R13. The oligo(oxyalkylene) acrylate is of formula: R1R2C=C(R3)C(=)Of(CHR4'CHR4"-O)m-R5 or R-(O-CH2CH2)n-O-C(=)-CHR'=CH2.R10-R12=H or 1-10C hydrocarbyl optionally containing heteroatoms;R13=aryl or heteroaryl;R1-R3=H or 1-10C hydrocarbyl;or R1+R3=ring;R4',R4"=H or methyl;R5=H, hydrocarbyl, acyl or silyl;m=2-100;R4',R4"=same or different groups;n=2-20;R=H or 1-6C alkyl;andR'=H or methyl.    TECHNOLOGY FOCUS - POLYMERS - Preferred Composition: The tapered copolymer region has end (e1) coupled to vinyl aromatic block and end (e2) coupled to oligo(oxyalkylene) acrylate block. The content of vinyl aromatic monomer in the tapered copolymer region varies gradually from the end (e1) to end (e2). The vinyl aromatic block is homopolymer of vinyl aromatic monomer. The vinyl aromatic block is obtained by polymerization of vinyl aromatic monomer which is same as vinyl aromatic monomer of the tapered copolymer region. Preferred Properties: The tapering profile in the tapered copolymer region shows increasing or decreasing content of vinyl aromatic monomer in the direction from A-B. The tapering profile in the tapered copolymer region shows sinusoidal and/or sawtooth variation. The oligo(oxyalkylene) acrylate block is homopolymer of oligo(oxyalkylene) acrylate monomer (a1), which may be the same as or different from oligo(oxyalkylene) acrylate monomer of the tapered copolymer region. The copolymer has taper volume fraction of 0.25-0.75, and overall vinyl aromatic monomer volume fraction content of 0.25-0.75. Preferred Process: Preparation of copolymer is done by anionic polymerization and atom transfer radical polymerization. The macroinitiators (i1,i2) are isolated and purified. The vinyl aromatic monomer (m2) and oligo(oxyalkylene) acrylate monomer (a1) are added to the reaction mixture using metered pumping.