Preparation and Properties of UV⁃curable Silicone Resin for LED Package

doi:10.19491/j.issn.1001-9278.2020.05.012

Abstract

Abstract:

A type of thiol?functionalized MDT silicone resin (MDT?SH) with different molecular structures was synthesized by hydrolysis?polycondensation, and then the MDT?SH was mixed with vinyl?functionalized silicone resin and photo?initiator to prepare a UV?curable silicone resin. The UV?curing kinetics of this UV?curable silicone resin was studied, and its thermal stability, transmittance and package performance were analyzed in detail. The results indicated that the MDT?SH exhibited a more uniform molecular weight distribution and a higher yield when synthesized at the R/Si molar ratio of 1.88/1 and the thiol content of 0.34 mol/100 g. The UV?curable silicone resin with a TPO?L dosage of 1.0 % and an SH/Vi molar ratio of 1.5/1 could be instantly cured when exposed to UV irradiation at 80 mW/cm². The UV?cured resin exhibited an excellent thermal stability and transmittance. The LED packaged by this UV?cured silicone resin also showed much better performance than those packaged by the Dow Corning OE?6550 commercial counterpart. The UV?curable silicone resin developed by this work shows a great potential in LED package in future.

Key words: ultraviolet?curing, thiol?functionalized silicone resin, light emitting diode package, thiol?ene photo?click reaction

CLC Number:

TQ322.4⁺1

Zhu LIU, Ziqian LIN, Hongping XIANG, Minzhi RONG, Mingqiu ZHANG. Preparation and Properties of UV⁃curable Silicone Resin for LED Package[J]. China Plastics, 2020, 34(5): 68-76.

Figures/Tables 12

References 15

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样品编号	KH580含量/g	DDS含量/g	MM含量/g	HCl含量^a）/g	H₂O含量^b）/g
SM?0.43	119.21（0.50 mol）	24.64（0.10 mol）	31.01（0.19 mol）	3.50	21.42（1.19 mol）
SM?0.39	143.05（0.60 mol）	49.28（0.20 mol）	36.54（0.22 mol）	4.58	27.72（1.54 mol）
SM?0.35	47.68（0.20 mol）	24.64（0.10 mol）	11.86（0.07 mol）	1.68	10.08（0.56 mol）
SM?0.26	23.84（0.10 mol）	24.64（0.10 mol）	5.52（0.03 mol）	1.08	6.30（0.35 mol）

样品编号	KH580含量/g	DDS含量/g	MM含量/g	HCl含量^a）/g	H₂O含量^b）/g
SM?0.43	119.21（0.50 mol）	24.64（0.10 mol）	31.01（0.19 mol）	3.50	21.42（1.19 mol）
SM?0.39	143.05（0.60 mol）	49.28（0.20 mol）	36.54（0.22 mol）	4.58	27.72（1.54 mol）
SM?0.35	47.68（0.20 mol）	24.64（0.10 mol）	11.86（0.07 mol）	1.68	10.08（0.56 mol）
SM?0.26	23.84（0.10 mol）	24.64（0.10 mol）	5.52（0.03 mol）	1.08	6.30（0.35 mol）

样品编号	MDT?SH		PSR?Vi含量/g	TPO?L含量/g ^b）
样品编号	类型	含量/g	PSR?Vi含量/g	TPO?L含量/g ^b）
UPA?1	SM?0.43	34.47（0.15 mol）	50.94 （0.10 mol ^a））	0.85
UPA?2	SM?0.39	39.28（0.15 mol）		0.90
UPA?3	SM?0.35	42.46（0.15 mol）		0.93
UPA?4	SM?0.26	57.41（0.15 mol）		1.08

样品编号	MDT?SH		PSR?Vi含量/g	TPO?L含量/g ^b）
样品编号	类型	含量/g	PSR?Vi含量/g	TPO?L含量/g ^b）
UPA?1	SM?0.43	34.47（0.15 mol）	50.94 （0.10 mol ^a））	0.85
UPA?2	SM?0.39	39.28（0.15 mol）		0.90
UPA?3	SM?0.35	42.46（0.15 mol）		0.93
UPA?4	SM?0.26	57.41（0.15 mol）		1.08

样品名称	巯基含量/mol·(100 g)^-1		M/D/T	R/Si	M_n^a）/g·mol^-1	M_w^b）/g·mol^-1	PDI ^c）	产率/%
样品名称	理论	实际	M/D/T	R/Si	M_n^a）/g·mol^-1	M_w^b）/g·mol^-1	PDI ^c）	产率/%
SM?0.43	0.43	0.40	0.78/0.23/1	1.83	1 541	1 957	1.27	73.82
SM?0.39	0.39	0.36	0.76/0.36/1	1.85	1 685	2 056	1.22	85.26
SM?0.35	0.35	0.34	0.73/0.51/1	1.88	1 329	1 568	1.18	90.16
SM?0.26	0.26	0.25	0.69/1.06/1	1.90	1 342	1 651	1.23	90.68