| 摘要 |
Visco-elastic tire balancing compositions comprising 1) 85 to 97% by weight of a glycol ether component comprising one or more ethylene/propylene glycol copolymer ethers of the general formula (I) or the general (II) or mixtures thereof R—O{[CH(CH3)CH2—O—]m[CH2—CH2—O—]n}H (I) R1—(O—{[CH(CH3)CH2—O—]m[CH2—CH2—O—]n}H)2 (II) wherein R is hydrogen or an alkyl group of 2-8 carbon atoms; R1 is an alkylene moiety of 2-8 carbon atoms in which the two substituents are not carried on the same carbon atom; m is the mole percentage of propylene glycol in the ethylene/propylene glycol copolymer moiety or moieties; and n is the mole percentage of ethylene glycol in the ethylene/propylene glycol copolymer moiety or moieties, wherein the ratio n:m is in the range from 35:65 to 80:20; each glycol copolymer compound having a number average molecular weight in the range of 2000-10000; and 2) 3 to 15% by weight of a fumed silica gel former; said balancing compositions being visco-elastic 1500 Pa and 5000 Pa at 22° C., a Loss Modulus (G″) smaller than the Storage Modulus up to a Cross Over Frequency of 10-40 Hz, and a Critical Yield Stress exceeding 2 Pa. |
