Kingfa Sci.&tech.co., Ltd.

Farouk Systems, Inc.

Huan Chang

Yong Xiao

Xianbo Huang

Nanbiao Ye

Min Cao

Chuanhui Zhang

Sujun Jiang

Kun Yan

Cheng Li

Zhongquan Peng

Xinxin Liu

Lei Tang

The invention discloses a flame-retardant semi-aromatic polyamide derived from the following monomers: a diacid monomer A: where A1 is terephthalic acid or terephthalic acid and other diacid, terephthalic acid accounts for 50 to 100 mol % of A1, and A2 is [(6-oxido-6H-dibenzo-(c,e)(1,2)-oxaphosphorin-6-ketone)-methyl]-butanedioic acid, A1+A2=100 mol %, A1=90 to 99 mol %, A2=1 to 10 mol %; and diamine monomer B: one or more of diamine monomers containing 4 to 36 carbon atoms. In the present invention, by an in situ polymerization, a specific flame-retardant monomer [(6-oxido-6H-dibenzo-(c,e)(1,2)-oxaphosphorin-6-ketone)-methyl]-butanedioic acid is copolymerized in a semi-aromatic polyamide chain segment, excellent mechanical properties and low water absorption can be obtained.

Flame-retardant semi-aromatic polyamide and preparation method thereof

A hair curler includes a curling iron assembly and comb tooth assembly arranged on the curling iron assembly. The curling iron assembly includes a heating body () and a metal sleeve () disposed around the heating body (), the metal sleeve () having a linear groove () formed in an outer surface of the metal sleeve (). The comb tooth assembly includes a comb tooth bar () disposed within the linear groove (), a recess () formed between a bottom wall of the linear groove and an interior portion of the comb tooth bar (), and a plurality of pivotal comb teeth () having an inserted portion () pivotally retained within the recess (), wherein the pivotal comb teeth () are movable relative to the comb tooth bar ().

Hot iron and curler with brush bristles

Growing community of inventors

Guangdong, China

Huan Chang