Effect of Modified Cellulose Nanocrystals on Crystallization Behavior of Polyamide 6

doi:10.19491/j.issn.1001-9278.2020.06.001

Abstract

Abstract:

A surface chemical reaction was conducted to prepare the isocyanate?modified cellulose nanocrystals (IPDI?CNC), and the resulting product was blended with polyamide 6 (PA6) to improve its crystallinity. The effects of pristine CNC and IPDI?CNC on the crystallization degree, crystallization kinetic parameters, and crystallization kinetics of PA6 were investigated by differential scanning calorimetry. The results indicated that IPDI?CNC exhibited better dispersibility in PA6 than CNC due to a significant improvement in crystallinity of PA6 as a result of the surface modification by IPDI. The non?isothermal crystallization process was studied by the Jeziorny’s method, and the results demonstrated that IPDI?CNC could act as a heterogeneous nucleating agent to improve the crystallization speed and crystalli?nity of PA6. Moreover, the addition of IPDI?CNC reduced the water absorption of PA6 by 71.4 % due to the increase of crystallization degree.

Key words: polyamide 6, modified?cellulose nanocrystals, isocyanate, crystallinity, water absorption

CLC Number:

TQ323.6

Jing ZHANG, Hong WANG, Wei ZOU, Zhongjie DU, Chen ZHANG. Effect of Modified Cellulose Nanocrystals on Crystallization Behavior of Polyamide 6[J]. China Plastics, 2020, 34(6): 1-6.

Figures/Tables 9

References 13

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名称	元素含量/%
名称	C	O	H	N
IPDI?CNC	43.96	48.68	6.63	0.73
CNC	40.93	52.72	6.35	—

名称	元素含量/%
名称	C	O	H	N
IPDI?CNC	43.96	48.68	6.63	0.73
CNC	40.93	52.72	6.35	—

样品名称	结晶度/%	T_m/℃
PA6	30.2	220.3
PA6/1 %CNC	43.6	221.5
PA6/5 %CNC	41.4	219.8
PA6/10 %CNC	35.6	219.4
PA6/1 % IPDI?CNC	43.9	220.5
PA6/5 % IPDI?CNC	47.8	221.4
PA6/10 % IPDI?CNC	43.8	221.7

样品名称	结晶度/%	T_m/℃
PA6	30.2	220.3
PA6/1 %CNC	43.6	221.5
PA6/5 %CNC	41.4	219.8
PA6/10 %CNC	35.6	219.4
PA6/1 % IPDI?CNC	43.9	220.5
PA6/5 % IPDI?CNC	47.8	221.4
PA6/10 % IPDI?CNC	43.8	221.7

样品	φ/℃?min^-1	T_p/℃	n	t_1/2/min	Z_c
PA6	5	190.44	5.043	3.30	0.261
	10	185.78	5.962	2.03	0.616
	15	179.85	4.996	1.73	0.789
	20	176.01	5.214	1.47	0.884
PA6/1 %CNC	5	198.61	5.546	1.67	0.476
	10	195.54	5.354	1.15	0.834
	15	191.92	4.388	0.98	0.937
	20	190.62	3.475	0.71	1.001
PA6/1 %IPDI?CNC	5	199.17	4.074	1.85	0.456
	10	196.32	3.858	1.03	0.864
	15	193.73	4.923	0.87	0.965
	20	192.41	4.98	0.70	1.028