以对甲基苯磺酸为催化剂，对甲基苯甲醛与对氯苯甲醛组成的混合醛和山梨醇为原料，合成了化学复合山梨醇缩醛类成核剂。在混合醛/山梨醇（摩尔比）2.05:1的条件下，分别合成了对氯苯甲醛与对甲基苯甲醛之比为1:0（E1）、4:1（E2）、3:1（E3）、2:1（E4）、1:1（E5）、1:3（E6）、1:4（E7）和0:1（E8）的复合成核剂，利用傅里叶红外光谱（FTIR）和X射线衍射（XRD），分别表征了成核剂的晶体结构和分子结构，FTIR测试显示合成的产物为山梨醇缩醛；XRD测试表明，采用复合醛合成的复合缩醛的晶体结构与E1不同。熔点测试发现，化学复合成核剂的熔点随原料中对甲基苯甲醛与对氯苯甲醛的摩尔比的增大而逐步提高。对聚丙烯的成核改性实验表明，化学复合成核剂具有增透和增刚的双重功能。

Chemical-composite sorbitol acetal nucleators were firstly synthesized with sorbitol, mixed with aldehydes of p-chlorobenzaldehyde (PCBA) and p-tolualdehyde (PTA) as raw materials and p-methyl benzenesulfonic acid as catalyst. Under the molecular ratio 2.05:1 of mixed-aldehydes to sorbitol, eight chemical-composite nucleators, with molar ratios 1∶0(E1), 4∶1(E2), 3∶1(E3), 2∶1(E4), 1∶1(E5), 1∶3(E6), 1∶4(E7), and 0:1(E8) of PBCA to PTA, respectively, were synthesized and their crystal and molecular structures were characterized by X-Ray Diffraction (XRD) and FTIR(Fourier transform infrared spectroscopy), separately. FTIR results show that synthetic products are sorbitol acetal, and XRD results indicate that the crystal structures of sorbitol acetal manufactured by mixed-aldhydes are different from E1 synthesied by PBCA. Melting point tests show that the MP of the chemical-composites decreases with the decrease of PBCA molar fraction within the reaction mixed aldehyde, and as a result, it will obviously reduce the processing temperature of polypropylene. The application experiments of nucleators synthesized in homopolypropylene(HOPP) show that the chemical-composites have enhanced HOPP stiffness and transparency simultaneously.