| 摘要 |
<p>The invention concerns a terephthalic polyester composition (CPT), comprising in mixture: an ethyleneterephthalate homooligomer (PET1) essentially containing recurrent terephthalate oxyethylene (TE) units; and a block terephthalate copolymer (PET2/TE-POE) containing at least a polyethyleneterephthalate (PET2) sequence; and at least a terephthalate polyoxyethylene (TE-POE) sequence whereof the POE unit has a molecular mass of 1500 to 4000 in number; said composition (CPT) being characterised in that: the quantity of (TE) units of (PET1) represents not more than 10 % of the total number of (TE) units present in said composition (CPT); the weight quantity of (TE) units present in the composition (CPT) represents at least 10 % of (TE) units present in the composition (CPT); the quantity by weight of mono(oxyethyleneoxy) radicals (OEO) represents at least 1.3 % of the weight of the composition (CPT), said radicals (OEO) belonging to the aromatic diester oxyethylene groups (ODA) of formula: -A-C(O)-O-CH2-CH2-O-C(O)-A- present in all the (PET1) and (PET2) sequences; and the molar mass by weight of block terephthalic copolymer (PET2/TE-POE) is at least 30000. Said composition is prepared by transesterification of a polyethylene terephthalate and a polyethylene glycol in the presence of magnesium oxide as catalyst. The invention also concerns the use of said composition as soil release agent in detergent formulations for washing textiles.</p> |
