Warpage Behaviors of System-in-Packages on a Substrate Strip

2018 ◽  
Vol 2018 (1) ◽  
pp. 000344-000348
Author(s):  
Eric Ouyang ◽  
Billy Ahn ◽  
SeonMo Gu ◽  
Jim Hsu ◽  
Yonghyuk Jeong ◽  
...  
Keyword(s):  
Material Characterization ◽  
Epoxy Resins ◽  
Curing Process ◽  
Molding Compound ◽  
Advanced Material ◽  
Curing Reaction ◽  
Different Types ◽  
The Impact ◽  
Compound Materials ◽  
Kinetics Of

Abstract In this paper, the impact of two different types of warpage, strip warpage and system-in-packages (SiP) module warpage, are considered and studied, both experimentally and numerically. An advanced material characterization method is also conducted to study the curing reaction and Pressure-Volume-Temperature-Cure (PVTC) kinetics of the packages. The curing reaction of epoxy resins, as a function of temperature and activation energies, is experimentally determined. During the curing process, the viscosity of epoxy resins change with temperature and conversion rate. The Castro-Macosko model is adopted to describe the rheological properties of epoxy resins. Experimentally, we have prepared substrate strip samples with different component density and molding compound materials. Each substrate strip contains eighteen system-in-packages. The warpages of all substrate strips and all the system-in-package modules were measured, compared, and correlated.

scholarly journals Curing Reaction Kinetics of the EHTPB-Based PBX Binder System and Its Mechanical Properties

Coatings ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1266
Author(s):  
Xing Zhang ◽  
Yucun Liu ◽  
Tao Chai ◽  
Zhongliang Ma ◽  
Kanghui Jia
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Reaction Kinetics ◽  
Testing Machine ◽  
Curing Process ◽  
Binder System ◽  
Isophorone Diisocyanate ◽  
Scanning Calorimetry ◽  
Curing Reaction ◽  
Kinetics Of

In this research, differential scanning calorimetry (DSC) was employed to compare the curing reaction kinetics of the epoxidized hydroxyl terminated polybutadiene-isophorone diisocyanate (EHTPB-IPDI) and hydroxyl terminated polybutadiene-isophorone diisocyanate (HTPB-IPDI) binder systems. Glass transition temperature (Tg) and mechanical properties of the EHTPB-IPDI and HTPB-IPDI binder systems were determined using the DSC method and a universal testing machine, respectively. For the EHTPB-IPDI binder system, the change of viscosity during the curing process in the presence of dibutyltin silicate (DBTDL) and tin 2-ethylhexanoate (TECH) catalysts was studied, and the activation energy was estimated. The results show that the activation energies (Ea) of the curing reaction of the EHTPB-IPDI and HTPB-IPDI binder systems are 53.8 and 59.1 kJ·mol−1, respectively. While their average initial curing temperatures of the two systems are 178.2 and 189.5 °C, respectively. The EHTPB-IPDI binder system exhibits a higher reactivity. Compared with the HTPB-IPDI binder system, the Tg of the EHTPB-IPDI binder system is increased by 5 °C. Its tensile strength and tear strength are increased by 12% and 17%, respectively, while its elongation at break is reduced by 10%. Epoxy groups and isocyanates react to form oxazolidinones, thereby improving the mechanical properties and thermal stability of polyurethane materials. These differences indicate that the EHTPB-IPDI binder system has better thermal stability and mechanical properties. During the EHTPB-IPDI binder system’s curing process, the DBTDL catalyst may ensure a higher viscosity growth rate, indicating a better catalytic effect, consistent with the prediction results obtained using the non-isothermal kinetic analysis method.

scholarly journals Present Status in Polymeric Mouthguards. A Future Area for Additive Manufacturing?

Polymers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1490 ◽  
Author(s):  
Ana M. Sousa ◽  
Ana C. Pinho ◽  
Ana Messias ◽  
Ana P. Piedade
Keyword(s):  
Additive Manufacturing ◽  
Impact Energy ◽  
Present Status ◽  
Material Characterization ◽  
Control Parameters ◽  
Contact Sports ◽  
Different Types ◽  
Manufacturing Techniques ◽  
The Impact ◽  
The Ideal

Athletes from contact sports are more prone to orofacial injuries because of the exposure to possible shocks and collisions derived from physical proximity. The use of protector polymeric mouthguards proved to be useful in the prevention of the described injuries. There are different types of mouthguards with varying ranges of protection and prices, but they are all made from polymers and share the same propose: to absorb and dissipate the impact energy resulting from the shocks. As they are used inside the mouth, they should not impair breathing and speaking nor compromise the comfort of the athlete. However, the ideal mouthguard is yet to be created. The choice of the most appropriate polymeric material and the standard required properties have not yet been reported. Regardless of the numerous studies in this field, normalized control parameters for both material characterization and mouthguard fabrication are absent. This paper aims to present a review of the current types of available mouthguards and their properties/characteristics. Moreover, a detailed description of the most common polymers for the fabrication of mouthguards, together with the manufacturing techniques, are discussed.

Study on Curing Mechanism of Azo-Containing Twin Liquid Crystalline Epoxy Resins with Anhydride

2013 ◽  
Vol 702 ◽  
pp. 119-122
Author(s):  
Teng Fei Shen ◽  
Fa Chao Wu ◽  
Ying Juan Sun
Keyword(s):  
Differential Scanning Calorimetry ◽  
Epoxy Resins ◽  
Liquid Crystalline ◽  
Curing Kinetics ◽  
Scanning Calorimetry ◽  
Curing Reaction ◽  
Azo Group ◽  
Liquid Crystalline Epoxy ◽  
Curing Mechanism ◽  
Kinetics Of

A series of novel azo-containing twin liquid crystalline (LC) epoxy monomers were cured with anhydrides without extra catalyst and the curing kinetics was investigated by non-isothermal differential scanning calorimetry (DSC) technique. The effect of Azo group on the Curing Kinetics of Epoxy/anhydride System was investigated and the result showed that Azo group served as a catalyst to accelerate the curing reaction. The curing mechanism was confirmed by the UV-Vis spectrum.

Curing Kinetics of Anisotropic Conductive Adhesive in the Manufacturing Process of RFID Tags

2013 ◽  
Vol 798-799 ◽  
pp. 17-24
Author(s):  
Shou Yuan Fan ◽  
Jian Kui Chen ◽  
Zhou Ping Yin
Keyword(s):  
Activation Energy ◽  
Curing Kinetics ◽  
Conductive Adhesive ◽  
Curing Process ◽  
Heating Rates ◽  
Degree Of Cure ◽  
Anisotropic Conductive Adhesive ◽  
Curing Reaction ◽  
Model Free ◽  
Kinetics Of

The study of the epoxy-based anisotropic conductive adhesive in electronic packaging interconnects applications (chip-on-glass, chip-on-flex, etc. especially in RFID applications) has received particular attention. This is due to its potential advantages of finer pitch printing, reducing environmental contamination. The thermal curing process is critical to develop the ultimate electrical and mechanical properties of the ACA devices. In this article, the curing kinetics of ACA was studied with a differential scanning calorimeter (DSC) under constant heating rates conditions in the range of 520 °C/min. The model free method was used to describe the curing reaction. The degree-of-cure and the activation energy through the whole conversion range were mathematically determined and used to predict the progress of the curing process. Experimental results show that the activation energy of the ACA varies significantly with degree-of-cure during the curing process. The peculiar phenomenon indicates that the ACA underwent a complex series of reactions. The kinetics of curing reaction changes when large conversion values are reached at low heating rates. The change in the reaction kinetics is due to vitrification of the ACA during heating. In addition, the degree-of-cure of the ACA as a function of bonding times during isothermal ACA bonding process was theoretically predicted.

Kinetic Studies on Epoxy Resins Cured with a Novel Polyamine

1992 ◽  
Vol 4 (1) ◽  
pp. 41-48 ◽  
Author(s):  
R. M. V. G. K. Rao ◽  
A. Padma ◽  
H. S. Patel
Keyword(s):  
Activation Energy ◽  
Epoxy Resin ◽  
Epoxy Resins ◽  
Kinetic Studies ◽  
Cure Kinetics ◽  
Curing Process ◽  
Kinetics Of

Differential scanning calorimeny was used to study the cure kinetics of three epoxy resin systems cured with two hardeners: diaminodiphenylmethane (DDM) and a poly (keto-amine) (PA). The results showved that the curing of the epoxy resins by PA occurs at higher temperatures and the activation energy for PA curing was higher compared with the DDM curing process, showing the er reactivity of PA.

scholarly journals Influence of Combustion Modifiers on the Cure Kinetics of Glycidyl Azide Polymer Based Propellant-Evaluated through Rheo-Kinetic Approach

Polymers ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 637 ◽  
Author(s):  
Liming He ◽  
Jun Zhou ◽  
Sulan Dai ◽  
Zhongliang Ma
Keyword(s):  
Measurement Method ◽  
Catalytic Effect ◽  
Cure Kinetics ◽  
Curing Process ◽  
Model Data ◽  
Glycidyl Azide Polymer ◽  
Rheological Measurement ◽  
Curing Reaction ◽  
Kinetics Of ◽  
Glycidyl Azide

To investigate the influence of combustion modifiers on the curing of glycidyl azide polymer spherical propellants (GAPSPs), the curing process of the GAPSPs was explored using an isothermal rheological measurement method. The parameters of cure kinetics were solved to further establish a kinetic model for the curing reaction of GAPSPs. The results showed that the curing process of GAPSPs under isothermal conditions conformed to the Kamal and LSK (Lu–Shim–Kim) models. The model data indicated significant agreement with the experimental data. The influence of four kinds of combustion performance modifiers on the curing process was explored and the results demonstrated that lead phthalate had a catalytic effect on the curing reaction of GAPSPs, whilst oxides of lead and copper, and copper adipate had no influence on the curing reaction.

scholarly journals Effect of an Anhydride Excess on the Curing Kinetics and Dynamic Mechanical Properties of Synthetic and Biogenic Epoxy Resins

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Facundo I. Altuna ◽  
Carmen C. Riccardi ◽  
Diana C. Marín Quintero ◽  
Roxana A. Ruseckaite ◽  
Pablo M. Stefani
Keyword(s):  
Epoxy Resins ◽  
Curing Kinetics ◽  
Dynamic Mechanical Properties ◽  
Diglycidyl Ether ◽  
Curing Agent ◽  
Curing Process ◽  
Optimal Amount ◽  
Efficient Processing ◽  
Kinetics Of ◽  
Methyltetrahydrophthalic Anhydride

This work analyzes the effect of the anhydride excess on the nonisothermal curing kinetics and on the final properties of synthetic and biobased epoxy resins. Diglycidyl ether of bisphenol A (DGEBA) and epoxidized soybean oil (ESO) were crosslinked using methyltetrahydrophthalic anhydride (MTHPA) as a curing agent and 1-methylimidazole (1MI) as an initiator. It was shown that the ESO/MTHPA/1MI system reacts slower than the DGEBA/MTHPA/1MI system, giving place to a more significant evaporation of the curing agent during the reaction. As a result, an excess of anhydride improves the final thermal properties of the ESO/MTHPA/1MI network, contrary to the behavior observed for DGEBA/MTHPA/1MI. The knowledge of the kinetics of the curing process and the optimal amount of the curing agent for each system is of critical importance for a more efficient processing of these materials.

Increasing Cryogenic Strength of Epoxy Resin Modified by Reactive Macroglycol

2011 ◽  
Vol 52-54 ◽  
pp. 2056-2059
Author(s):  
Da Hu Yao ◽  
Yu Qing Zhang ◽  
Joong Hee Lee
Keyword(s):  
Impact Strength ◽  
Bisphenol A ◽  
Epoxy Resin ◽  
Epoxy Resins ◽  
Cryogenic Temperature ◽  
Room Temperature ◽  
Curing Process ◽  
Epoxy Network ◽  
The Impact ◽  
Modified Epoxy

A bisphenol-A glycidol ether epoxy resin was toughened in cryogenic temperature using reactive macroglycol as modifiers. The properties of modified epoxy resin were characterized by SEM and DMA. Phase-separated structure formed during curing process in the PPG and PTMG modified epoxy resins system, and did not occurred in the PEO modified epoxy resins system. The impact strength of epoxy resin increased at both room temperature (RT) and cryogenic temperature (CT, 77 K) using PEO as modifier. The DMA results confirm that the introduction of PEO chains in the structure of the epoxy increases the mobility of the molecular segment of epoxy network at both RT and CT.

Quota Women Are Threatening to Men

2017 ◽  
Vol 76 (3) ◽  
pp. 107-116 ◽  
Author(s):  
Klea Faniko ◽  
Till Burckhardt ◽  
Oriane Sarrasin ◽  
Fabio Lorenzi-Cioldi ◽  
Siri Øyslebø Sørensen ◽  
...  
Keyword(s):  
Decision Making ◽  
Organizational Performance ◽  
Gender Stereotypes ◽  
Perceived Threat ◽  
Preferential Treatment ◽  
Public Sector Employees ◽  
Different Types ◽  
Low Levels ◽  
Women In Decision Making ◽  
The Impact

Abstract. Two studies carried out among Albanian public-sector employees examined the impact of different types of affirmative action policies (AAPs) on (counter)stereotypical perceptions of women in decision-making positions. Study 1 (N = 178) revealed that participants – especially women – perceived women in decision-making positions as more masculine (i.e., agentic) than feminine (i.e., communal). Study 2 (N = 239) showed that different types of AA had different effects on the attribution of gender stereotypes to AAP beneficiaries: Women benefiting from a quota policy were perceived as being more communal than agentic, while those benefiting from weak preferential treatment were perceived as being more agentic than communal. Furthermore, we examined how the belief that AAPs threaten men’s access to decision-making positions influenced the attribution of these traits to AAP beneficiaries. The results showed that men who reported high levels of perceived threat, as compared to men who reported low levels of perceived threat, attributed more communal than agentic traits to the beneficiaries of quotas. These findings suggest that AAPs may have created a backlash against its beneficiaries by emphasizing gender-stereotypical or counterstereotypical traits. Thus, the framing of AAPs, for instance, as a matter of enhancing organizational performance, in the process of policy making and implementation, may be a crucial tool to countering potential backlash.

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