玻璃纤维增强体形式对酚醛泡沫性能的影响

针对酚醛泡沫脆性大、强度低等缺点,采用3种不同增强形式的玻璃纤维增强体,即短切玻璃纤维(SGF)、酚醛树脂浸渍固化的玻璃纤维针(GFN)及三维间隔连体织物,对酚醛泡沫进行增强.研究了纤维含量和纤维长度对酚醛泡沫压缩性能的影响规律,对比了不同增强形式纤维增强酚醛泡沫复合材料的压缩性能与保温性能.结果表明:当SGF长度为3 mm,与基体质量比为5%时,SGF增强酚醛泡沫的比压缩强度最佳,较纯泡沫的提高了21%;GFN(长度5 mm,与基体质量比为25%)增强酚醛泡沫的比强度提高8%;三维间隔连体织物增强酚醛泡沫的比强度虽略有下降,但其压缩强度(0.239 MPa)达到了承重类酚醛泡沫的要求.SGF和GFN增强的酚醛泡沫的热导率与纯酚醛泡沫的相比略有上升,但仍符合高效保温材料的要求;三维间隔连体织物增强酚醛泡沫的热导率上升明显.

Effects of glass fiber reinforcement type on property of phenolic foam

Aiming at the defects of phenolic foam, such as brittleness and low strength, three kinds of glass fiber reinforcement with different forms, i.e. short chopped glass fiber (SGF), glass fiber needle with phenolic resin impregnated and cured (GFN) and 3D spacer grille fabric with phenolic resin impregnated and cured, were adopted to reinforce phenolic foam. The effects of fiber content and length on the compressive property of phenolic foam were studied. The compressive and thermal insulation properties of phenolic foams reinforced by different glass fibers were compared. The results indicate that phenolic foam reinforced by 5% mass ratio of SGF with 3 mm length has the largest specific compressive strength, which increases by 21% than pure foam. Specific compressive strength of phenolic foam reinforced by 25% mass ratio of GFN with 5 mm length increases by 8%. Specific compressive strength of phenolic foam reinforced by 3D spacer grille fabric slightly reduces, while its compressive strength (0.239 MPa) meets the requirement of load-bearing phenolic foam. Compared with phenolic foam without fibers, the thermal conductivities of phenolic foams reinforced by SGF or GFN are a bit higher, but still meet the requirement of efficient thermal insulation materials, while the thermal conductivity of phenolic foams reinforced by 3D spacer grille fabric increases apparently.