Effect of addition of PE⁃LD on anti⁃sag performance of bimodal polyethylene

doi:10.19491/j.issn.1001-9278.2025.06.002

Abstract

Abstract:

To address the sagging resistance of HDPE100S， this study introduces a blending strategy utilizing low⁃density polyethylene （PE⁃LD）， leveraging its long⁃chain branching characteristics. The impact of PE⁃LD incorporation on the rheological and anti⁃sagging properties of HDPE100S was systematically evaluated using melt flow index， capillary rheometry， and rotational rheometry. The experimental results indicated that the addition of PE⁃LD had negligible impact on the melt flow rate （MFR） of HDPE100S. Significant increases in processing torque， zero⁃shear viscosity， and relaxation time were observed， indicating enhanced melt elasticity and sagging resistance. Differential scanning calorimetry analysis further elucidated the influence of PE⁃LD on the crystallization and melting behavior of HDPE100S. These results demonstrate that PE⁃LD acts as an effective rheological modifier， improving the anti⁃sagging performance of HDPE100S without compromising its flowability during processing.

Key words: bimodal polyethylene, low density polyethylene, rheological behavior, anti?sagging performance, melting crystallization behavior

CLC Number:

TQ325.1⁺2

JIN Yucheng, WANG Jingfan, ZHAO Shicheng. Effect of addition of PE⁃LD on anti⁃sag performance of bimodal polyethylene[J]. China Plastics, 2025, 39(6): 6-9.

Figures/Tables 7

Fig.1. The effect of PE⁃LD content on the MFR of HDPE100S

Fig.2. Minilab test results of the HDPE100S samples

Fig.3. Schematic diagram of the molecular structures of PE⁃LD

Fig.4. Rheological test results of the HDPE100S samples

样品	η₀/×10⁵Pa·s	λ/s
HDPE100S	1.95	32.9
HDPE100S/0.5%PE⁃LD	2.25	34.4
HDPE100S/1%PE⁃LD	2.44	43.9
HDPE100S/2%PE⁃LD	2.79	70.6

Tab.1. Rheological parameters of the samples with different PE⁃LD concentrations

Fig.5. DSC test of HDPE100S/PE⁃LD blends

样品	熔融峰温度/℃	结晶峰温度/℃
HDPE100S	131.2	116.9
HDPE100S/0.5%PE⁃LD	130.8	117.4
HDPE100S/1%PE⁃LD	131.7	116.4
HDPE100S/2%PE⁃LD	134.1	112.7

Tab.2. DSC test results of HDPE100S/PE⁃LD blends

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