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乙烯基改性聚苯醚遥爪低聚体在非环氧体系覆铜板中的应用

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乙烯基改性聚苯醚遥爪低聚体在非环氧体系覆铜板中的应用

第十三届中国覆铜板技术交流会

作者： Edward N.Peters scott m.fisher 郭桦黄欣那莹 Alfred Ng SABIC Innovative Plastics(沙伯基础创新塑料有限公司)

便携式高频微电子设备的发展对电子材料的性能提出了更高的要求,比如更低的介电常数(Dk)、更低的损耗角正切值(Df)、低吸湿性及良好的热稳定性等。环氧树脂广泛应用于电子工业,反应型聚苯醚遥爪低聚体与其配合使用可使其性能大幅提升。...

便携式高频微电子设备的发展对电子材料的性能提出了更高的要求,比如更低的介电常数(Dk)、更低的损耗角正切值(Df)、低吸湿性及良好的热稳定性等。环氧树脂广泛应用于电子工业,反应型聚苯醚遥爪低聚体与其配合使用可使其性能大幅提升。但环氧树脂介电性能的局限性,推动非环氧基介电材料成为新的研究热点。后者优异的性能被用于满足更高的性能需求。本文重点研究了乙烯基单体,如三烯丙基异氰脲酸酯(TAIC)和叔丁基苯乙烯/二乙烯基苯(TBS/DVB)及其与乙烯基改性聚苯醚遥爪低聚体配合使用及性能提升。众所周知,TAIC和TBS/DVB热固性材料表现为脆性,但是使用乙烯基改性聚苯醚遥爪低聚体,使材料在性能上显著提高,如良好韧性、非常低的介电常数和损耗角正切值、高玻璃化转变温度(Tg)和极低的吸湿性等。本文详细研究了多种乙烯基单体与乙烯基改性聚苯醚遥爪低聚体配合使用,所制成的覆铜板性能与环氧树脂及改性环氧树脂相比表现出显著的性能优势。

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NORYLTm SA90与SA9000树脂在热固性电子材料中的性能研究

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NORYLTM SA90与SA9000树脂在热固性电子材料中的性能研究

第十九届中国覆铜板技术研讨会

作者： Eylem TarkinTas Parminder Agarwal Edward N.Peters scott m.fisher 孔凡旺 SABIC Specialties(沙比克特材部门) 沙比克特材热固性及添加剂部中国区

SA9000树脂是低分子量双官能PPE低聚物,专门设计用于各种热固性树脂和弹性体。NORYL低聚物由于其固有的特性、在常规溶剂中的高溶解度以及独特的功能性,在降低介电性能、提高玻璃化转变温度和增强韧性以及降低吸湿性方面均提供了良好的... 详细信息

SA9000树脂是低分子量双官能PPE低聚物,专门设计用于各种热固性树脂和弹性体。NORYL低聚物由于其固有的特性、在常规溶剂中的高溶解度以及独特的功能性,在降低介电性能、提高玻璃化转变温度和增强韧性以及降低吸湿性方面均提供了良好的改善,非常适合于电子材料应用,特别是印刷电路板。本文综述了NORYL SA90和SA9000树脂在不同热固性体系中对电子材料的性能评估。

关键词：聚苯醚低聚物介电常数介电损耗热固性材料

多官能团聚苯醚低聚物在覆铜板中的应用及无卤阻燃性能的研究

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多官能团聚苯醚低聚物在覆铜板中的应用及无卤阻燃性能的研究

第十一届中国覆铜板技术·市场研讨会

作者： Edward N.Peters scott m.fisher 郭桦郭舰潘胜平 Alfred Ng Sabic Innovative Plastices沙伯基础创新塑料有限公司通用电气中国研发中心有限公司

在电子工业中,由于近年来对环境保护的日益重视和各种规范的要求,无卤阻燃已经越来越普遍.然而,无卤阻燃的成本较高,与含溴阻燃剂相比一般加入量要求较大,甚至对性能产生影响.基于上述原因,有必要开发价格便宜对性能影响低的无卤阻燃体... 详细信息

在电子工业中,由于近年来对环境保护的日益重视和各种规范的要求,无卤阻燃已经越来越普遍.然而,无卤阻燃的成本较高,与含溴阻燃剂相比一般加入量要求较大,甚至对性能产生影响.基于上述原因,有必要开发价格便宜对性能影响低的无卤阻燃体系。本文研究了在环氧树脂中加入反应性的低分子量聚(2,6-二甲基-1,4二苯基醚)的树脂体系的情况.聚苯醚的高度芳香化结构使其不易燃烧,它与磷系阻燃剂也具有良好的协同阻燃效果.因此,聚苯醚和环氧树脂体系可以降低磷系阻燃剂的的用量;同时减免阻燃剂对基材物理机械性能的负面影响。在无卤环氧树脂中加入聚苯醚行成均相的交联网络,可以提高材料韧性的同时提高玻璃化转变温度,提高介电性能,降低吸水性。

关键词：聚苯醚无卤阻燃环氧树脂介电材料

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Sabic添加剂在电子行业中的应用

Sabic添加剂在电子行业中的应用

第二十届中国覆铜板技术研讨会

作者： Eylem Tarkin Tas Yasser Dhahir Lucas Bufalini Edward N.Peters Bimal Patel scott m.fisher 孔凡旺 SABIC Specialties (沙比克特材部门)

电子行业应用中,一系列热塑性及热固性材料可经由沙比克反应型添加剂增强其性能,例如覆铜板(CCL),这些添加剂可应用于环氧体系,氰酸酯体系,过氧化物或聚酰亚胺体系。可显著改善介电性能,降低吸水率,提高耐热性及增加韧性。本文将着重探... 详细信息

电子行业应用中,一系列热塑性及热固性材料可经由沙比克反应型添加剂增强其性能,例如覆铜板(CCL),这些添加剂可应用于环氧体系,氰酸酯体系,过氧化物或聚酰亚胺体系。可显著改善介电性能,降低吸水率,提高耐热性及增加韧性。本文将着重探讨相应体系及其应用技术数据。

关键词：聚苯醚低聚物介电常数介电损耗热固性材料酸酐

关于多官能聚苯醚低聚体增强介电材料性能的研究(一)

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覆铜板资讯 2009年第3期 37-40页

作者： Edward N.Peters scott m.fisher 郭桦潘胜平 Sabic Innovative Plastics One Noryl Avenue Selkirk NY 12158 USA

当前印刷电路板呈现出两大趋势,即应用于较高的工作频率和装配中使用无铅焊,因此对介电材料的要求更苛刻,主要表现在:低介电常数、低介电损耗、高使用温度、低吸水性。热塑性材料——聚苯醚(PPE)的使用被证明能有效地提升热固性材料的性... 详细信息

当前印刷电路板呈现出两大趋势,即应用于较高的工作频率和装配中使用无铅焊,因此对介电材料的要求更苛刻,主要表现在:低介电常数、低介电损耗、高使用温度、低吸水性。热塑性材料——聚苯醚(PPE)的使用被证明能有效地提升热固性材料的性能,如优秀的耐水解性能、低吸水性、极高的玻璃化温度、在较宽的温度和频率范围内杰出的电性能,以及无需卤素阻燃剂就可达到良好的阻燃性能。研究显示,在热固性材料中使用热塑性材料,充分固化后的材料可取得多种的相态,分子交联网络结构呈现出复杂性。据报道,在广泛增强介电材料性能的材料研究中,多官能团聚苯醚低聚体取得了突破性进展。这种多官能团聚苯醚低聚体作为大分子单体可和环氧树脂反应并提升其多种性能。

关键词：聚苯醚多官能团聚苯醚低聚体环氧树脂热塑性材料

Stomatal dynamics are regulated by leaf hydraulic traits and guard cell anatomy in nine true mangrove species

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Plant Diversity 2024年第3期46卷 395-405页

作者： Ya-Dong Qie Qi-Wei Zhang scott A.m.mcAdam Kun-Fang Cao State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources College of ForestryGuangxi UniversityNanning 530004China Guangxi Key Laboratory of Forest Ecology and Conservation College of ForestryGuangxi UniversityNanning 530004China Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection Ministry of EducationGuangxi Normal UniversityGuilin 541001China Guangxi Key Laboratory of Landscape Resources Conservation and Sustainable Utilization in Lijiang River Basin Guangxi Normal UniversityGuilin 541001China Purdue Center for Plant Biology Department of Botany and Plant PathologyPurdue UniversityWest LafayetteIN 47907USA

Stomatal regulation is critical for mangroves to survive in the hyper-saline intertidal zone where water stress is severe and water availability is highly ***,very little is known about the stomatal sensitivity to vapour pressure deficit(VPD)in mangroves,and its co-ordination with stomatal morphology and leaf hydraulic *** measured the stomatal response to a step increase in VPD in situ,stomatal anatomy,leaf hydraulic vulnerability and pressure-volume traits in nine true mangrove species of five families and collected the data of genome *** aimed to answer two questions:(1)Does stomatal morphology influence stomatal dynamics in response to a high VPD in mangroves?with a consideration of possible influence of genome size on stomatal morphology;and(2)do leaf hydraulic traits influence stomatal sensitivity to VPD in mangroves?We found that the stomata of mangrove plants were highly sensitive to a step rise in VPD and the stomatal responses were directly affected by stomatal anatomy and hydraulic ***,denser stomata was correlated with faster stomatal closure at high VPD across the species of Rhizophoraceae,and stomata size negatively and vein density positively correlated with genome *** negative leaf osmotic pressure at the full turgor(πo)was related to higher operating steady-state stomatal conductance(gs);and a higher leaf capacitance(Cleaf)and more embolism resistant leaf xylem were associated with slower stomatal responses to an increase in *** addition,stomatal responsiveness to VPD was indirectly affected by leaf morphological traits,which were affected by site salinity and consequently leaf water *** results demonstrate that mangroves display a unique relationship between genome size,stomatal size and vein packing,and that stomatal responsiveness to VPD is regulated by leaf hydraulic traits and stomatal *** work provides a quantitative framework to better understand of stomatal regulation in mangroves

关键词： Stomatal temporal kinetics Vapour-pressure deficit(VPD) Leaf water relations Leaf hydraulic vulnerability Leaf osmotic potential Genome size

ATP-binding cassette transporters as possible targets for the intervention of neurodegenerative diseases

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Neural Regeneration Research 2024年第4期19卷 721-722页

作者： Hiu Chuen Lok Glenda m.Halliday Woojin scott Kim Brain and mind Centre&School of medical Sciences The University of SydneySydneyNSWAustralia

ATP-binding cassette(ABC)transporters are ubiquitous membrane-bound proteins that are responsible for the translocation of a broad spectrum of substrates across cellular membranes,including lipids,amino acids,nucleosides,sugars,and ***,ABC transporters are highly expressed in the *** their functions in the brain still need to be elucidated,several members are implicated in the pathogenesis of neurodegenerative diseases,including Alzheimer’s disease(AD),Parkinson’s disease(PD),and frontotemporal *** this perspective,we will review current knowledge of ABC transporters in the central nervous system in terms of physiological functions and pathology in ***,we will explore the possibilities of ABC transporters as potential targets in the development of therapeutics for neurodegenerative diseases.

关键词： sugar degenerative diseases

Cannabinoids and endocannabinoids as therapeutics for nervous system disorders:preclinical models and clinical studies

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Neural Regeneration Research 2024年第4期19卷 788-799页

作者： R.scott Duncan Sean m.Riordan matthew C.Gernon Peter Koulen Department of Ophthalmology School of MedicineUniversity of Missouri Department of Biomedical Sciences School of MedicineUniversity of Missouri

Cannabinoids are lipophilic substances derived from Cannabis sativa that can exert a variety of effects in the human *** have been studied in cellular and animal models as well as in human clinical trials for their therapeutic benefits in several human *** of these include central nervous system(CNS)diseases and dysfunctions such as forms of epilepsy,multiple sclerosis,Parkinson’s disease,pain and neuropsychiatric *** addition,the endogenously produced cannabinoid lipids,endocannabinoids,are critical for normal CNS function,and if controlled or modified,may represent an additional therapeutic avenue for CNS *** review discusses in vitro cellular,ex vivo tissue and in vivo animal model studies on cannabinoids and their utility as therapeutics in multiple CNS *** addition,the review provides an overview on the use of cannabinoids in human clinical trials for a variety of CNS *** and endocannabinoids hold promise for use as disease modifiers and therapeutic agents for the prevention or treatment of neurodegenerative diseases and neurological disorders.

关键词： anandamide cannabidiol cannabinoid endocannabinoid epilepsy multiple sclerosis neurodegeneration neuroprotection tetrahydrocannabinol

Adaptation in brain structure and respiratory and olfactory structures across environmental gradients in African and North American muroid rodents

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Integrative Zoology 2024年第1期19卷 165-181页

作者： Peter J.TAYLOR Aluwani NENGOVHELA Christiane DENYS Graham R.scott Catherine m.IVY Department of Zoology School of Natural and Mathematical SciencesUniversity of VendaThohoyandouSouth Africa Afromontane Unit Department of Zoology and EntomologyUniversity of the Free StatePhuthaditjhabaSouth Africa Department of mammalogy National MuseumBloemfonteinSouth Africa Institut de Systématique EvolutionBiodiversité(ISYEB)Muséum National d’Histoire NaturelleCNRSSorbonne UniversitéEPHEUniversitéDes AntillesParisFrance Department of Biology McMaster UniversityHamiltonOntarioCanada Guglielmo and Shoemaker Labs Advanced Facility for Avian ResearchUniversity of Western OntarioLondonOntarioCanada

morphometric studies of 3D micro CT-scanned images can provide insights into the evolution of the brain and sensory structures but such data are still scarce for the most diverse mammalian order of *** reviewed and new data,we tested for convergence to extreme aridity and high elevation in the sensory and brain morphology of rodents,from morphometric data from micro-CT X-ray scans of 174 crania of 16 species of three distantly re-lated African murid(soft-furred mice,Praomyini,laminate-toothed rats,Otomyini,and gerbils,Gerbillinae)clades and one North American cricetid(deer mice and white-footed mice,Peromyscus)*** studies demon-strated convergent evolution acting on the oval window area of the cochlea(enlarged in extremely arid-adapted species of Otomyini and Gerbillinae)and on endocranial volume(reduced in high elevation taxa of Otomyini and Peromyscus).However,contrary to our predictions,we did notfind evidence of convergence in brain struc-ture to aridity,or in the olfactory/respiratory system(turbinate bones)to high *** structure differed,particularly in the petrosal lobules of the cerebellum and the olfactory bulbs,between Otomyini and Gerbillinae,with extreme arid-adapted species in each clade being highly divergent(not convergent)from other species in the same *** observed greater“packing”of the maxillary turbinate bones,which have important respiratory functions,in Peromyscus mice from high and low elevations compared to the high-elevation African Praomyini,but more complex patterns within Peromyscus,probably related to trade-offs in respiratory physiology and heat exchange in the nasal epithelium associated with high-elevation adaptation.

关键词： 3D morphometrics Africa brain size North America Rodentia sensory evolution