Page 94 - 《橡塑技术与装备》英文版2026年3期

HINA R&P TECHNOLOGY AND EQUIPMENT

Table 2 Thermal decomposition data of KNFs, mKNFs @ of EPDM is 2.01×10-4 mol/cm3. Compared to EPDM, the
@
@
SiO 2 , and KKNFs SiO 2 crosslinking density of 5-mKNFs SiO 2 /EPDM is increased
T 5 /℃ T 10 /℃ T max /℃ R 800 /% @
KNFs 541.7 562.8 584.7 39.29 by 0.21%, and that of 5-KKNFs SiO 2 /EPDM is increased
@
@
mKNFs SiO 2 275.8 430.3 606.3 74.64 by 61.60%. The enhancement effect of KKNFs SiO 2 is more
@
KKNFs SiO 2 198.2 371.8 610.2 64.01
pronounced. This is due to the difficulty in forming effective
@
SiO 2 is more pronounced. This is due to the γ-aminopropyl crosslinking points between mKNFs SiO 2 and EPDM. The
@
groups introduced by KH550, which enhance the wetting and modification with KH550 enables KKNFs SiO 2 2 to disperse
penetration of the nanofibers into the rubber, forming a dense uniformly within the EPDM matrix, and the van der Waals
and stable interpenetrating network between the nanofibers and interaction between it and the EPDM matrix forms new
the rubber. This creates a hybrid interfacial layer of EPDM- physical crosslinking points in the system, thus significantly
KH550-KNFs, thereby improving the adhesion between improving the crosslinking density of the composite material.
@
the rubber and KKNFs SiO 2 . The increase in bound rubber Figure 3(b) shows that the crosslinking density of EPDM
content in the rubber results in KKNFs SiO 2 enhancing is 2.20×10-4 mol/cm3. With the increase in the content of
@
@
@
EPDM rubber more effectively. Figure 3(b) shows that as KKNFs SiO 2 , the crosslinking density of 1-KKNFs SiO 2 /
@
@
the content of KKNFs SiO 2 increases from 0 to 5 parts, the EPDM and 3-KKNFs SiO 2 /EPDM increases by 3.5% and
BdR of KKNFs SiO 2 /EPDM rapidly increases. This is due 9.4%, respectively, which is not significant. This is because the
@
to the good interfacial interaction formed by the physical grafted KH550 cannot react with the EPDM molecular chain
@
crosslinking between KKNFs SiO 2 and the EPDM matrix, to form chemical bonds, thus failing to form effective chemical
and the interaction continues to strengthen as the content of crosslinking points. The crosslinking density of 5-KKNFs @
@
KKNFs@SiO2 increases. Additionally, after adding 7 parts of SiO 2 /EPDM and 7-KKNFs SiO 2 /EPDM increases by 61.7%
KKNFs@SiO2, the change in the system's BdR is relatively and 68.1%, respectively. This is due to the prominent role of
@
small, which may be due to a certain degree of agglomeration KKNFs SiO 2 as physical crosslinking points when its addition
of the nanofibers in the rubber matrix. amount is high.
As can be seen from Figure 3(a), the crosslinking density

Figure 3 Combined rubber content and crosslinking density of KKNFs SiO 2 /EPDM
@
@
2.3 Mechanical properties elongation at break of 5-mKNFs SiO 2 /EPDM are increased
As shown in Figure 4(a), the tensile strength and by 89.4% and 30.2%, respectively. This is due to the in-
elongation at break of EPDM are 5.88 MPa and 463%, situ growth of nano-SiO 2 on the surface of mKNFs SiO 2 ,
@
respectively. Compared to EPDM, the tensile strength and which increases the specific surface area of the nanofibers.

·48· Vol.52，No.3