Page 48 - 《橡塑技术与装备》英文版2025年12月

HINA R&P TECHNOLOGY AND EQUIPMENT

Study on the properties of liquid silicone rubber with

different foaming agents during the foaming and

addition molding process

Zhang Jie, Zhang Hong, Chang Shiwen
(Shenyang Baoshun'an Safety Equipment Co. LTD., Shenyang, Liaoning 110000)

Abstract: The addition-type liquid silicone rubber was foamed using physical foaming agents, sodium
bicarbonate as a foaming aid, and hollow glass microspheres, respectively, to obtain foamed silicone rubber.
This paper deeply investigated the effects of three foaming aids and their different dosages on the foaming
effect, and conducted characterization and testing of the structure and properties of the successfully
prepared foamed silicone rubber. The research results showed that the foaming effect of the foamed silicone
rubber prepared using physical foaming agents was more ideal, and medium-foaming foam materials could
be prepared; the tensile strength and elongation increased with the increase in the density of the foamed
silicone rubber; the pressure during molding has a significant impact on the foaming effect, and the foaming
ratio increased as the pressure decreased.
Key words: addition-type liquid silicone rubber; foaming agent; foamed silicone rubber; foaming ratio;
tensile strength
Classification number: TQ330.387 Article number: 1009-797X (2025)12-0042-06
Document code: B DOI: 10.13520/j.cnki.rpte.2025.12.010

Foam silicone is a porous material with a silicone base these materials typically utilize condensation dehydrogenation
that contains numerous air bubbles. It possesses lightweight, reactions. Su Junjie et al. used deionized water and hydrogen-
sound insulation, heat insulation, impact load absorption, containing silicone oil to generate gas under platinum catalysis,
sealing, shock absorption, and other properties, and is widely and prepared foamed silicone using vinyl silicone oil. There
used in national defense, aerospace, transportation, electronics, are relatively few research reports on the foaming of liquid
agriculture, and daily necessities. silicone with foaming aids.
Currently, the molding technologies for silicone foam This article uses addition-type liquid silicone rubber
materials primarily include precipitation pore-forming as the matrix, selects different foaming agents, and employs
molding, chemical foaming molding, hybrid foaming molding, the molding process to obtain foamed silicone rubber. The
and physical foaming molding. The matrix of silicone foam appropriate foaming agent is determined by measuring the
materials can be made from high molar mass solid silicone foaming effect, mechanical properties, and morphology.
or liquid silicone. Currently, the preparation of silicone
foam materials via the liquid method mainly involves room 1 Experimental part
temperature vulcanized silicone foam materials, with the gas 1.1 Experimental materials
source primarily coming from internal blowing agents, such The addition-type liquid silicone is in a two-component
as the reaction between Si—OH or R—OH and Si—H, which form, with the main agent and crosslinking agent equally
produces H2 to promote internal foaming in the system. Tan
Yu et al. reviewed the research progress of room temperature Biography: Zhang Jie (1980-), a senior engineer with a bachelor's degree,
vulcanized silicone foam materials in recent years, noting that primarily engaged in research related to materials.

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